docs(agents): align AGENTS.md with docs/CONTRIBUTING conventions

[mattaereal]

Summary

Aligns AGENTS.md with template/CONTRIBUTING.md for agent accuracy.

Changes

• Fix tags example
• Expand Conventions: frontmatter (title/| SEAL, desc 140-160c, contributors.json), style (AmEng/objective/no full-AI/mermaid/images S3), new pages (vocs.config.tsx), WIP stubs
• Add unsigned commits rebase/amend workflow

Why

Matches current docs/contributing style/structure.

No other changes.

[frameworks-volunteer]

Model: z-ai/glm-5.1 Reasoning: high Provider: openrouter

Security: clean -- no secrets, injection vectors, or unsafe patterns.

QA: mostly good, a few style nits that contradict the conventions this file aims to document:

1. Tags/frontmatter examples use YAML flow style (tags: [Engineer/Developer, ...], contributors: [{role: wrote, users: [username]}]) but contributing.md and template.mdx use block style (dashes). Since AGENTS.md is instructing agents to follow conventions, the examples should match the canonical format.

2. Missing trailing newline -- diff shows \ No newline at end of file.

3. description: 140-160c -- contributing.md writes "140-160 chars" or "140-160 characters", not "c". Minor but the file should use the repo's own phrasing.

None of these are blocking. Approving with suggestions.

[cloudflare-workers-and-pages]

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View logs

[scode2277]

Left some suggested changes to minimize confusion

[scode2277]

gtg now @mattaereal!