Validate meetup image sources at build time (#142)

[alexwolson]

Closes #142.

Adds _scripts/validate_images.sh (with _scripts/test_validate_images.sh), exposed as make validate and run on pull requests via ci.yml. It checks that every meetup's image: front matter resolves to a file in archives/images/events/, skipping external http(s) URLs, and exits non-zero on a missing source. This is the guard that would have caught #549 before it shipped.

Scope is meetups only — projects use external image URLs and organizations' image: is unrendered and lives in the main repo (see the design doc). pages.yml and make generate are untouched, so production deploys are never gated by this check.

What's here

• _scripts/validate_images.sh — set -euo pipefail, ARCHIVES_DIR-overridable, guards a missing meetups dir, skips empty/http(s) values, exits 1 on any miss.
• _scripts/test_validate_images.sh — fixture-based tests: present→0, missing→1 (names the file), external-URL→0, CRLF→0. All pass locally.
• Makefile — make validate target (kept out of make generate).
• .github/workflows/ci.yml — Validate meetup image references step on PRs to main, between generate and build.
• Docs in README.md / CLAUDE.md, plus the design spec and implementation plan under docs/superpowers/.

Dependency / sequencing

This check correctly fails on the pre-existing #549 (hacknight_549.avif) until #141 (CivicTechTO/archives#26) is merged and the archives submodule pointer is updated. The red Validate meetup image references check on this PR is the expected, correct signal that the guard works — not a defect to fix by weakening the check. CI goes green once the #549 fix is in the pinned submodule commit.

🤖 Generated with Claude Code

[alexwolson]

Note that the failing check above is demonstrating that this PR works as intended.

[Khasir]

Thanks again!

[github-actions]

Pa11y Accessibility Report

✅ All pages passed — 0 warning(s) (WCAG2AA)

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Homepage

✅ No issues found.

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Event

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Project

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Person

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Organization

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Venue

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Resource

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Tag

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Category

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