Added support for the JetBrains AI Assistant

[befresh-mweimerskirch]

Description

This PR adds support for displaying the quota from the JetBrains AI Assistant.

Type of Change

• Bug fix
• New feature
• New provider plugin
• Documentation
• Performance improvement
• Other (describe below)

Testing

• I ran bun run build and it succeeded
• I ran bun run test and all tests pass
• I tested the change locally with bun tauri dev

Screenshots

Checklist

• I read CONTRIBUTING.md
• My PR targets the main branch
• I did not introduce new dependencies without justification

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Summary by cubic

Added a JetBrains AI Assistant provider plugin that reads the local IDE quota cache and shows quota, used, remaining, and reset timing.

• New Features
  • Reads AIAssistantQuotaManager2.xml from JetBrains IDE config dirs on macOS, Linux, and Windows; refined macOS platform checks.
  • Picks the latest window; breaks ties by usage; fills missing fields.
  • Supports tariff/top-up buckets and converts JetBrains units (1e-5) to credits.
  • Shows Quota (percent with reset), Used, and Remaining; sets periodDurationMs when available.
  • Adds host.fs.listDir to the plugin API with safer error handling (throws on open, skips bad entries); updates docs and README.
  • Unit tests for parsing, scaling, path discovery (incl. Windows), duration parsing, and error cases.

^{Written for commit f56e13d. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 9 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="plugins/jetbrains-ai-assistant/plugin.json">

<violation number="1" location="plugins/jetbrains-ai-assistant/plugin.json:7">
P3: plugin.json references icon.svg but there is no icon.svg in the plugin directory (or anywhere under plugins/), so the icon path will not resolve at runtime.</violation>
</file>

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[davidarny]

Thanks! LGTM!

[Copilot]

Pull request overview

Adds a new provider plugin to surface JetBrains AI Assistant quota by reading the local JetBrains IDE quota cache, and extends the plugin host filesystem API to support directory discovery needed for locating the quota file.

Changes:

• Added jetbrains-ai-assistant provider plugin (implementation, manifest, icon) to parse AIAssistantQuotaManager2.xml and emit Quota/Used/Remaining lines.
• Extended the plugin Host FS API with host.fs.listDir() and updated plugin API docs accordingly.
• Added unit tests for parsing, selection logic, scaling, duration parsing, and error cases; documented the new provider and linked it from the README.

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src-tauri/src/plugin_engine/host_api.rs	Exposes host.fs.listDir() to plugins (with ~ expansion) to support filesystem discovery.
plugins/test-helpers.js	Enhances test FS mocks to emulate directory existence and implement listDir() for plugin tests.
plugins/jetbrains-ai-assistant/plugin.test.js	Adds Vitest coverage for parsing/selection/scaling/duration/error handling for the new plugin.
plugins/jetbrains-ai-assistant/plugin.json	Registers the new provider plugin metadata and declared UI lines.
plugins/jetbrains-ai-assistant/plugin.js	Implements JetBrains quota discovery + XML/JSON parsing and line generation.
plugins/jetbrains-ai-assistant/icon.svg	Adds provider icon asset referenced by the plugin manifest.
docs/providers/jetbrains-ai-assistant.md	Documents data sources, parsed fields, displayed lines, and error messages for the provider.
docs/plugins/api.md	Documents the new host.fs.listDir() API and provides a usage example.
README.md	Adds JetBrains AI Assistant to the list of supported providers.

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[validatedev]

LGTM!