feat(vscode): add setting to toggle token/cost counter visibility

[awhite0030]

Description

Brief description of what this PR does

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Changeset

• Added a changeset (pnpm changeset) describing this change for the changelog

Docs-only or internal chores need no changeset (or run pnpm changeset --empty to note that intentionally).

Testing

Automated Tests

• New features include passing tests in .spec.ts/tsx files
• All existing tests pass (pnpm test:all completes successfully)
• Tests cover both success and error scenarios

Manual Testing

• Tested with Ollama
• Tested with OpenRouter
• Tested with OpenAI-compatible API
• Tested MCP integration (if applicable)

Checklist

• If this was for an open issue, I was assigned to it
• Code follows project style guidelines
• Self-review completed
• Documentation updated (if needed)
• No breaking changes (or clearly documented)
• Appropriate logging added using structured logging (see CONTRIBUTING.md)

---

Root cause: The token and cost counter is shown unconditionally, which creates visual noise for some users.
Fix: Added a VS Code setting nanocoder.showTokenUsage (defaulting to false) and plumbed it into the webview payload so that the UI only renders the counter when enabled. Created a changeset.
Validation: Ran pnpm run build, pnpm test:format, pnpm test:lint, pnpm test:types, pnpm test:knip, and targeted tests pnpm test:ava plugins/vscode/src/. All passed. Validated changeset logic with node scripts/validate-changesets.js.
Fixes #1096

Fixes #1096

[will-lamerton]

Thanks for picking this up. The setting itself is right (default: false matches what #1096 asked for, and workspace.getConfiguration is the correct source here rather than SettingsManager, which models agents.config.json). One blocker though.

Blocker: this reverts #1098

The branch predates 8a46cd3 ("restore usage footers when reopening chats"), which added a second call site for appendUsageIndicator in the history-replay path. Only the live-turn call site is updated, so after merging main:

plugins/vscode/media/chat-panel.js
2065:  function appendUsageIndicator(usage, cost, showTokenUsage) {
2429:      appendUsageIndicator(replayedUsage, replayedUsage.cost);        // 2 args, never gated
2446:      appendUsageIndicator(update.usage, update.cost, update.showTokenUsage);

Line 2429 passes no third argument, so showTokenUsage is undefined, the new guard bails, and reopened chats lose their token/cost line permanently even with the setting on. Merging origin/main into this branch (clean merge) and running the existing spec confirms it:

✘ [fail]: replayed response usage metadata restores the token and cost line
  source/vscode/chat-panel-turn-footer.spec.ts:102
  Value is not truthy: undefined

CI is green only because the branch has not been rebased.

Suggested fix: gate once, off syncState

Attaching the flag to the per-turn ACP update payload is why the replay path was missed, and it has two more costs: it only arrives on prompt_response/done, so toggling the setting does nothing until the next completed turn (no onDidChangeConfiguration listener, though the pattern exists at extension.ts:130 and acp-client.ts:47), and it mixes a UI preference into the ACP message shape.

Pushing it once over syncState (chat-webview-provider.ts:112, handled at chat-panel.js:2162) into a module-level variable read inside appendUsageIndicator fixes the replay bug and the live-toggle gap together, and leaves the signature unchanged.

Also

• No tests. source/vscode/chat-panel-harness and chat-panel-turn-footer.spec.ts already drive this renderer and assert on the usage line, so on/off across both the live and replay paths is a few lines.
• The changeset targets nanocoder-vscode, which is in the ignore list in .changeset/config.json, so changeset status bumps nothing and this ships with no changelog entry. validate-changesets.js passes because the name is a real workspace package. #1098, also VS Code only, used "@nanocollective/nanocoder": patch.

[github-actions]

Hi @awhite0030, thanks for this PR! It looks like a maintainer has left feedback
or review activity and there are still some outstanding items to wrap up.

Whenever you get a chance, could you take a look at the open comments?
If anything is unclear or you'd like a hand, just reply here and we'll help you get it across the line.