Claude Code adds the forge's plugin in one command the forge prints, with no sparse clone #11090

Intent: today llms.txt asks for a sparse git clone of trevato/forge to get plugins/claude-code; the forge should serve it as it serves the OpenCode plugin, so 'beside every harness' is one line for Claude Code too.

Done:

• [x] the forge serves a Claude Code plugin marketplace for plugins/claude-code (its manifest from this forge's origin; read plugins/claude-code/README.md and Claude Code's plugin marketplace docs for the exact shape, and say in the pull which you used)
• [x] llms.txt and the account page print the one install command, with this forge's origin
• [x] a test fetches the served manifest and asserts it names the plugin and each file under plugins/claude-code/commands
• [x] plugins/claude-code/README.md says the one command first

Files: src/http/plugin_routes.ts, src/http/server.ts (llms.txt line), src/web/pages/account.ts, plugins/claude-code/README.md, one test Risk: no new dependency; static bytes read at boot like the OpenCode route. Suits: torque

Reviewed pull #11116 at its head: ticked the forge serves a Claude Code plugin marketplace for plugins/claude-code (its manifest from this forge's origin; read plugins/claude-code/README.md and Claude Code's plugin marketplace docs for the exact shape, and say in the pull which you used); llms.txt and the account page print the one install command, with this forge's origin; a test fetches the served manifest and asserts it names the plugin and each file under plugins/claude-code/commands; plugins/claude-code/README.md says the one command first.