chore(framework): type issues instead of labelling them

[blafourcade]

🎯 What & why

The issue forms applied labels: ["bug"] and labels: ["enhancement"]. Neither label exists on GitHub, so both directives were silently dropped: zero of the repo's 300 issues carries either one. Issue types (Bug, Feature, Task) are defined at the org level, and issue forms support a top-level type: key.

🛠️ How it works

• Both forms swap labels: for type:. bug_report.yml sets type: Bug, feature_request.yml sets type: Feature.
• Titles carry a scope. fix(<scope>): and feat(<scope>): , matching the scope commitlint.config.cjs already expects on the commit that closes the issue.
• New roadmap.yml for maintainer-authored work: Problem, Scope, Acceptance criteria required; Prior art in this repo and Out of scope optional. No Code of Conduct checkbox, no OS dropdown — those belong on a contributor intake form, not on a roadmap item. The two optional sections are the ones that surfaced duplicates during the backlog triage that prompted this PR.
• labels.yml drops bug, enhancement, documentation, security. Types replace them. What survives is what a bot or a human actually reads: good first issue, dependencies (dependabot), autorelease: * (release-please).

The dependencies label was missing on GitHub too, so dependabot dropped it on every PR (#401, #400, #399, #398, #362 all landed unlabelled). It has been created out-of-band; the GitHub label set now matches labels.yml exactly.

🧪 How to verify

# every template parses, and none applies a label
for f in .github/ISSUE_TEMPLATE/*.yml .github/labels.yml; do yq e '.' "$f" >/dev/null && echo "OK $f"; done
grep -r '^labels:' .github/ISSUE_TEMPLATE/ ; echo "exit=$?  # 1 = no label left"

# live label set equals the canonical list
gh label list --repo ai-driven-dev/framework | cut -f1 | sort
yq e '.[].name' .github/labels.yml | sort

Then open https://github.com/ai-driven-dev/framework/issues/new/choose: three forms, each stamping a type.

✅ I certify

• I DO CERTIFY I READ EACH LINE OF THE PULL REQUEST BECAUSE I AM A SOFTWARE ENGINEER, NOT A AI PUPPY.