feat(tools-box): introduce tools modal with builtin tools, mcp, and subagents

[spoons-and-mirrors]

Introduce the tool box

This feature rich PR provides users with fine-grained control over their Agent's capabilities while maintaining a clean, intuitive interface that integrates seamlessly with the existing TUI experience. Deprecating #1767

UX Enhancements

• Granular: The dialog lets users tailor an agent's complete toolkit without changing global configurations.
• Clean UX: Toggle anything on or off, the dialog visually distinguishes between default and overridden settings, making it clear how the agent's behavior has been modified.
• Agent-Specific Configurations: Users can switch between primary agents with the dialog opened (pressing tab) to manage toolsets independently for each one.
• Fuzzy: Search matches "mcp" and "subagent" categories
• Persisted: Tool config persists to state and is session(conversation) and agent scoped

Issues

Resolves #1142

[github-actions]

This violates the AGENTS.md guideline: AVOID using any type. Consider: Use a more specific type like Record<string, { name: string; description: string; type: string; source: string; defaultEnabled: boolean }>

File: packages/opencode/src/agent/agent.ts
Line: 143

[github-actions]

This violates the AGENTS.md guideline: AVOID using any type. Consider: Use a more specific type like Record<string, { name: string; description: string; type: string; source: string; defaultEnabled: boolean }>

File: packages/opencode/src/mcp/index.ts
Line: 158

[github-actions]

This violates the AGENTS.md guideline: AVOID using any type. Consider: Use a more specific type like Record<string, { name: string; description: string; type: string; source: string; defaultEnabled: boolean }>

File: packages/opencode/src/tool/registry.ts
Line: 92

[github-actions]

This violates the AGENTS.md guideline: AVOID else statements. Consider: Restructure this if-else block to avoid the else clause by returning early or using separate conditional blocks.

File: packages/opencode/src/session/index.ts
Around lines 817-830 in the diff (the else block in the agent description replacement logic)

[thdxr]

OK quick thoughts

• i see what you did with unifying under the concept of resource but i think we should leave them as separate things. basically make a tool endpoint and reuse the existing agent endpoint. i'm factoring in some plans we have for other clients with this + sync engine things

• for agent overrides - i think we should track this durably in the session? that way if you switch back to the session it's the same config? i'm actually planning on getting rid of mode of the state() in the Session module

[spoons-and-mirrors]

Heard. @thdxr

[spoons-and-mirrors]

all done !