chore: apply dotnet format baseline and add CI gate

[ottobolyos]

Summary

• dotnet format MTConnect.NET.sln --verify-no-changes currently fails against master, with formatting drift (mostly tab/space indentation) spread across 61 files, concentrated in MTConnect.NET-Common, MTConnect.NET-HTTP and the build/ tooling projects. Applies dotnet format once to bring the tree back to zero-diff against dotnet format's SDK-default formatting rules. The repo does not yet ship a root .editorconfig, so the enforced ruleset is whatever the SDK pinned by actions/setup-dotnet treats as its whitespace / C# formatting defaults; committing a root .editorconfig (plus a global.json SDK pin) to freeze the rules against future SDK drift is a tracked follow-up (see below).
• Adds a format job to .github/workflows/dotnet.yml that runs dotnet format MTConnect.NET.sln --verify-no-changes --verbosity diagnostic on every push to master and every non-draft pull request targeting it, so this drift cannot silently reaccumulate. The --verbosity diagnostic flag names each offending file and rule directly in the CI log when the gate fires, so a contributor can reproduce and fix locally without further tooling.
• Adds four sibling per-project steps (restore + verify) for the two csprojs that ship with the dotnet new mtconnect.net-agent template but are not members of MTConnect.NET.sln; both are public-surface artifacts for downstream template consumers, so their formatting is user-facing and belongs under the same gate.
• Refactors build/MTConnect.NET-DocsGen/RouteInventory.cs::CeenHandlerParameters to hoist each handler's EndpointParam[] into a dedicated private static readonly field. The prior shape (an inline new EndpointParam[] { ... } nested inside a dictionary object initializer) tripped dotnet format into a non-idempotent indent cascade — the outer dictionary keys deepened by four spaces while the inner block stayed at the old depth. Hoisting the arrays flattens both layers to the same indent depth and keeps dotnet format a no-op on the file.
• Documents the new gate on docs/testing/workflows.md (steps, --severity warn rationale, local-reproduction command), and adds a top-level CONTRIBUTING.md so GitHub's contributor-guidelines banner surfaces the formatting + test invocations on new-PR / new-issue forms.
• No behavioral change: dotnet build succeeds cleanly on the formatted tree; the whole-tree diff is whitespace / indentation only apart from the one RouteInventory.cs refactor above (verified by comparing whitespace-stripped diff lines on every other touched file).

Scope note on --severity

dotnet format with no --severity flag defaults to warn, which covers whitespace and style diagnostics — that is what was applied here and what the new CI job checks. --severity info additionally attempts to auto-fix long-standing Roslyn analyzer diagnostics (CA1859, CA1861, CA1018, etc.) across the whole repository; on the SDK used to prepare this branch that full-tree run terminates with NotSupportedException: Changing document properties is not supported before completing. Analyzer-diagnostic cleanup is a materially different, larger piece of work from formatting drift, so it is deliberately left out of scope here; the CI gate mirrors the same default severity.

Follow-ups (not in this PR)

• Root .editorconfig + global.json SDK pin: the gate currently relies on dotnet format's SDK-default ruleset. Committing a root .editorconfig that freezes the enforced rules, plus a global.json that pins the SDK, would insulate the gate from future .NET 8 / 9 patch releases that shift a formatting default and silently re-fire the gate on unchanged code.
• Required status check: for this gate to actually block merges, the new format job needs to be added to the branch-protection required-status-check list for master. I don't have branch-protection edit rights, so a maintainer will need to enable it after this merges.
• Pre-commit hook: the repository has no lefthook, husky, or pre-commit tooling installed, so a hook that runs dotnet format on staged files before commit is left as a follow-up rather than bundled here (adding a hook framework is a separate, more invasive change deserving its own PR and review).
• NuGet cache + workflow-level concurrency block: broader CI-hygiene wins that would speed the format job (and every other job) up on cache-hit and cancel superseded runs on the same PR. Scoped to a dedicated CI-hygiene PR rather than folded into this format-baseline change.

Dime review cycle 1

Agent	Findings	Disposition
code-review	1 MEDIUM (missing .editorconfig vs PR-body claim), 1 LOW (out-of-sln template csprojs)	CLOSED in cycle-1 fix commit 8c542429 — workflow comment now reflects SDK-default ruleset; template csprojs added to gate scope.
security-audit	none	—
simplification	none	—
improvement	2 MEDIUM (--verbosity diagnostic; missing .editorconfig), 3 LOW (README pointer; NuGet cache; workflow-level concurrency)	CLOSED (--verbosity diagnostic applied; README + CONTRIBUTING.md pointers added). .editorconfig and CI-hygiene items TRACKED as follow-ups above.
documentation-audit	1 HIGH (docs/testing/workflows.md missing format-job entry), 1 MEDIUM (no dotnet format guidance for developers)	CLOSED — ### Job 0 — format subsection added; README + CONTRIBUTING.md guidance added.
test-coverage-audit	none	—

Dime review cycle 2

Agent	Findings	Disposition
code-review	1 LOW (typography — ASCII hyphen in ### Jobs 1-4 heading)	CLOSED in cycle-2 fix commit d7353b7b — en-dash applied.
security-audit	none	—
simplification	none	—
improvement	1 MEDIUM (RouteInventory.cs indent cascade baked in by the format run), 2 LOW (missing CONTRIBUTING.md; template steps grouped into two run: blocks)	CLOSED — CeenHandlerParameters refactored to hoist parameter arrays into named fields (dotnet format now idempotent on the file); CONTRIBUTING.md added; template steps split into four per-project named steps for CI-log granularity.
documentation-audit	1 MEDIUM (PR body still asserted the .editorconfig claim contradicted by the new docs)	CLOSED — this PR body edit rewrites the Summary bullet to match the docs and the workflow comment.
test-coverage-audit	none	—

Dime review cycle 3

Retro-fresh cycle at the current tip bb41a02a (was fc328332 at cycles 1-2), triggered by the merge-train position-discipline rule requiring dime cycles at the current head, not at an earlier completed_head_sha.

Agent	Findings	Disposition
code-review	2 LOW (added-line BrE tokens artefact/artefacts in .github/workflows/dotnet.yml comment block; artefacts/cataloguing in the earlier commit's message body)	FIXED in the cycle-3 rebase-rewrite (commit 549b3dd9 → 4164ba1e) — American English mandate on committed content overrides the LOW ceiling; workflow comment lines 50, 79 now use artifact / artifacts; commit body now uses artifacts / cataloging. Pre-existing BrE on workflow lines 461, 543 stays untouched (already on master, out of this PR's diff scope).
security-audit	none	—
simplification	2 LOW (README.md Contributing block still lists commands rather than pointer-only to CONTRIBUTING.md; four per-template restore + verify steps could collapse to two per-template combined steps)	CLOSED with rationale — README self-contained shape aids drive-by browsers who never open CONTRIBUTING.md; separate restore + verify steps let Actions surface per-phase timing in the step-summary panel, keeping diagnostic value. Both are proposals with the reviewer's own false-positive defence covering the current shape.
improvement	2 MEDIUM (no timeout-minutes on the new format job / any workflow job; workflow-level concurrency block deferred), 2 LOW (fetch-depth: 1 pin on actions/checkout; _ceenSummaryCache as ConcurrentDictionary for future concurrent callers)	CLOSED with rationale — timeout-minutes and workflow-level concurrency both belong in the deferred CI-hygiene follow-up PR listed under "Follow-ups (not in this PR)" above (alongside NuGet cache), not folded into this format-baseline scope. fetch-depth: 1 matches the current actions/checkout@v4 default (no behavioural change). _ceenSummaryCache is only ever populated from single-threaded DocsGen invocations; the race is theoretical.
documentation-audit	none	—
test-coverage-audit	none	RouteInventory.cs refactor is behaviour-preserving; the byte-exact docs/reference/http-api.md assertion in DocsReferenceGenerationTests.HttpApi_Page_Is_In_Sync_With_Source transitively pins every hoisted EndpointParam[] field's content — any drift would fail the assertion.

Dime review cycle 4

Delta-only cycle at tip bb41a02a verifying the cycle-3 rebase-rewrite: 4 word-swaps in comments and a commit body, second commit rebased on top. No behavioural, logical, or algorithmic change; second commit content byte-identical to its cycle-3 form.

Agent	Findings	Disposition
code-review	none	Cycle-3 BrE findings verified Fixed. Both commits %G? = G. No new leaks.
security-audit	none	Word-swaps are comment-only, no run: / env: / ${{ }} / ref: surface change; no secrets introduced.
simplification	none	No structural change; cycle-3 dispositions stand.
improvement	none	No new opportunities from the rebase-rewrite; cycle-3 dispositions stand.
documentation-audit	none	Added-line BrE grep returns 0; pre-existing carve-out lines untouched.
test-coverage-audit	none	Zero test-code delta from the rebase.

(Zero unfixed findings — Ready-eligible.)

[ottobolyos]

@PatrickRitchie — #219 merged, promoting #230 as new queue head. Cycles ≥2 clean; CI green; ready for your review.