ADFA-6279 | Show connected capabilities as tags under chat input

[jatezzz]

Description

This PR introduces a live-updating row of capability tags under the chat input, replacing the static backend label. These tags provide users with immediate visibility into the agent's connected backend (including the active model name), web access status, and available tool sources (such as MCP servers and plugin tools). It also implements health probing across the MCP and OpenAI plugins, allowing the tags to reflect degraded states (e.g., unreachable servers or invalid API keys) in real-time, and resolves them automatically when the connection recovers.

Details

• UI Updates: Added capability_tag_scroll and capability_tag_group to fragment_chat.xml. Implemented CapabilityTagRowController to manage rendering, tapping (for details/settings), and long-pressing (for tooltips) of the tags.
• Core capabilities: Added CapabilityMonitor and CapabilityReaders in AI-Core to manage the live state of backends and tool registries.
• Backend & Tool Plugins: Updated Gemini, Local LLM, OpenAI, and MCP plugins to implement ActiveModelReportingBackend and/or StatusReportingBackend. Introduced ServerHealth and McpServerHealth to track and broadcast connectivity status.
• Lifecycle simplification: Migrated backend plugins to use LlmBackendRegistration rather than manually managing AI Core lifecycle listeners.
• Compatibility: Bumped plugin.min_ide_version to 26.41 across all affected plugins to support the new capability tag contracts.

Screen_Recording_20261002_172542_Code.on.the.Go.mp4

Screen_Recording_20261002_172715_Code.on.the.Go.mp4

Ticket

ADFA-6279

Observation

The tag row operates reactively using Flow collection, meaning it updates automatically when network connectivity changes, a server goes down, or a backend is switched. The individual plugins handle their own background polling (like the PROBE_INTERVAL_MS for MCP servers) to report degraded states without blocking the UI thread.

[Daniel-ADFA]

Reviewed at fd1e8fa.

CRITICAL

• GeminiPlugin.kt:5 - the new plugin-api contract is not in libs/plugin-api.jar, so the PR does not compile

IMPORTANT

• McpPlugin.kt:240 - servers that refused the token are re-probed every 20s
• OpenAiBackend.kt:334 - the health recheck polls every 30s forever, even when OpenAI is not selected

addons has no written approve/request-changes rule (checked CLAUDE.md), so the default rule applied.