feat(chat): tabbed model selector with agent segmented control

[tlgimenes]

What is this contribution about?

Redesigns the chat-input model selector to remove repetition and add explicit agent switching:

• Agent segmented control (new) — sits to the left of the model pill in the chat input, lets users switch between Decopilot / Claude Code / Codex with one click. Hidden when the active agent has no clonable source (no desktop CLI option) or only one section is eligible. Laptop agents get a small green dot + sr-only "on desktop".
• Model selector popover — collapsed to a clean 3-row tier picker (Fast / Smart / Thinking) for the active agent. Single-line rows, right-aligned muted descriptions, taller padding, narrower container that hugs the rows (overrides the default w-72 baked into shared PopoverContent).
• Claude Code labels carry their versions: Haiku 4.5, Sonnet 4.6, Opus 4.7.
• Side fix: the AI-provider connect dialog used sm:max-w-3xl for every state — its OAuth-pending / provision-pending / provision-error states now use sm:max-w-md so the "Authorize the connection in the popup window…" message no longer floats inside a giant box.

Screenshots/Demonstration

(internal — verified locally in the conductor workspace)

How to Test

1. Open a chat for an agent with a clonable source (e.g. New Website with a branch). The chat input now shows a segmented control to the left of the model pill — switch between Decopilot / Claude Code / Codex and confirm the model pill icon/label and the popover reflect the choice.
2. Open the model pill. Confirm a tight 3-row picker (Fast / Smart / Thinking with versioned Claude rows). Click each row and confirm the tier updates.
3. Open a chat for a non-clonable agent (Decopilot-only). The segmented control is hidden; the model pill still opens the same 3-row picker.
4. From AI provider settings, trigger an OAuth flow. The "Authorize the connection in the popup window…" dialog is now narrow instead of full-width.

Migration Notes

Not applicable.

Review Checklist

• PR title is clear and descriptive
• Changes are tested and working
• Documentation is updated (if needed)
• No breaking changes

🤖 Generated with Claude Code

---

Summary by cubic

Redesigned the chat model selector: agent choice is now a second select pill next to the model pill, and the popover is a compact three-tier picker for the active agent. Also narrowed the provider connect dialog in pending/error states and versioned Claude Code labels.

• New Features

  • Added a harness select pill (Decopilot / Claude Code / Codex) next to the model pill; hidden when the agent isn’t clonable or there’s only one option. The closed pill shows the active harness; CLI options show a small green dot, and popover rows include an sr-only “on desktop”.
  • The model selector popover shows a single section with three tiers (Fast / Smart / Thinking); no tabs. Right‑aligned descriptions, taller row padding, and w-auto popover with an inner w-72 container. Dropped the redundant “On” tag.
  • Updated Claude Code labels to include versions: Haiku 4.5, Sonnet 4.6, Opus 4.7.
  • Selecting a CLI agent while on a branch now eagerly starts the VM for a faster first response.

• Bug Fixes

  • Provider connect dialog uses sm:max-w-md for OAuth/provision pending and error states to avoid oversized layouts.

^{Written for commit 33677e7. Summary will update on new commits. Review in cubic}

[github-actions]

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[github-actions]

Release Options

Suggested: Minor (2.341.0) — based on feat: prefix

React with an emoji to override the release type:

Reaction	Type	Next Version
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🚀	Major	3.0.0

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[cubic-dev-ai]

2 issues found across 13 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="apps/mesh/src/web/components/chat/agent-model-popover.tsx">

<violation number="1" location="apps/mesh/src/web/components/chat/agent-model-popover.tsx:34">
P2: Fallback section rendering can lose the selected tier highlight when `activeAgent` is missing. Use `activeTier` for the rendered section so the picker always shows a selected row.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

P2: Fallback section rendering can lose the selected tier highlight when activeAgent is missing. Use activeTier for the rendered section so the picker always shows a selected row.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At apps/mesh/src/web/components/chat/agent-model-popover.tsx, line 34:

<comment>Fallback section rendering can lose the selected tier highlight when `activeAgent` is missing. Use `activeTier` for the rendered section so the picker always shows a selected row.</comment>

<file context>
@@ -9,45 +9,39 @@ interface Props {
+    return <div className="flex flex-col gap-1 w-60" />;
+  }
+
+  const selectedTier = section.kind === activeAgent ? activeTier : null;
 
   return (
</file context>

Suggested change

	const selectedTier = section.kind === activeAgent ? activeTier : null;
	const selectedTier = activeTier;