Generate website release, compatibility, install, and tool metadata from canonical sources

[Railly]

Context

The deployed website has several independently hardcoded facts that have drifted:

• Landing and changelog advertise v0.7.4 while manifest.json is v0.8.0.
• Docs claim Obsidian 1.4.11 while the manifest requires 1.7.2.
• Manual installation targets ~/.obsidian/plugins/agentfiles/ instead of a vault directory.
• Public copy phrases the canonical total of 17 as additional tools.
• The Supported Tools table lists only seven tools.

Task

Extend the existing build-time metadata sync to derive release version, minimum Obsidian version, tool roster, and documentation rows from repository sources. Correct manual installation to use <vault>/.obsidian/plugins/agentfiles/.

Acceptance criteria

• Landing, changelog, docs, metadata, and supported-tools table agree with canonical files.
• Tool-count copy treats 17 as the total.
• Manual installation creates and targets an explicit vault plugin directory.
• CI fails when public release or tool metadata drifts.
• The deployed pages show the current values after merge.