[eviweb]

docs(rules): add experimental CI triggers template

Distilled from a real fix applied to a personal project's
.github/workflows/ci.yml, which had on: push: / pull_request:
with no filters — triggering on every ref push (including tags,
redundant with CI already run on the main commit a tag points at),
every PR regardless of target, and every file change regardless of
content.

• New rules/ci-triggers-template.md, explicitly marked experimental
  and not yet part of rules/ci.md's mandatory checklist: scope
  push to main/develop/conventional branch prefixes, scope
  pull_request to PRs targeting main, add the workflow_dispatch
  • concurrency group already required by rules/ci.md but easy to
    forget, and skip lint/test via job-level if: (not a
    trigger-level paths-ignore) when a push/PR only touched docs —
    the job-level approach keeps the workflow always reporting, so a
    required status check never gets stuck waiting on a workflow that
    never ran
• Assumes GitHub Flow (direct-to-main) as the default branching model
  per rules/git.md — a two-tier develop/main model is kept as an
  opt-in, not the default, since it defers integration feedback
  without a proportional benefit for most projects
• CHANGELOG.md / TODO.md updated; not yet wired into rules/ci.md —
  intended to be applied manually on a couple more real projects
  first, then promoted to the mandatory checklist if it holds up

Tests: 104/104 passing (adding an unreferenced rules/*.md file has no
test surface — nothing in this repo's suite enumerates or validates
the rules/ directory's contents against CLAUDE.md's @rules/
references).