[hetaoBackend]

Change

Plugin management was documented only as “Use /plugins to manage extensions,” while the capability table could be read as promising GitHub imports from the CLI/TUI. Add the panel shortcuts, shell commands, source selectors, and local-directory workflow, and state the limits: only official and local selectors exist, local packages are discovered rather than installed with plugin add, and arbitrary marketplace registration / GitHub URL import are not exposed.

Related to #193. This addresses the documentation gap; it does not implement or close the request for arbitrary marketplace management.

Validation

• PASS: pnpm verify --profile docs on clean commit ce6c660 (macOS, Node 26.4.0): source inventory, generated paths, committed-source export, release tools (20 passed; 1 Windows-only test skipped). The shared classifier identifies both changed files as documentation-only.
• PASS: pnpm build; inspected the built plugin, plugin add, and plugin marketplace help.
• PASS: existing plugin application and TUI manager tests, 2 files / 14 tests.
• PASS: built CLI in an isolated temporary profile with a synthetic plugin and outbound network denied: marketplace listing, local discovery, disable, enable, expected LOCAL_PLUGIN_INSTALL_UNSUPPORTED on local add, removal, and empty readback. Verified that removal deleted the installed directory and no outbound network attempt occurred.
• NOT RUN: live official catalog mutations, interactive terminal end-to-end acceptance, Linux/Windows execution, and full runtime verification profile (documentation-only change).

Publication and contribution checks

• I have permission to contribute these changes under the existing licenses applicable to the changed files/packages; no imported material.
• No credentials, account data, real user content, internal source history or private review material is included.
• Existing files only; no inventory regeneration or new tests required.
• English usage and capability documentation updated; shared README content unchanged. Offline results are not described as live-service acceptance.

Maintainer handoff

Publication scope or license changes: none.

Shared-source port: not needed (public usage documentation only).

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