docs: update README What's New for v2.71 and add Ecosystem section

Add post-release fixes (model selection hardening, credential cooldown
recovery, TUI improvements, provider fixes) and GSD2 Config Utility link.

README.md

@@ -40,12 +40,34 @@ One command. Walk away. Come back to a built project with clean git history.
 - **isError flag propagation** — workflow tool execution failures now correctly return `isError: true`, so MCP clients can distinguish success from failure.
 - **Multi-round discuss questions** — new-project discuss phase supports multi-round questioning with structured question gates.
 
-### TUI Fixes
+### Model Selection Hardening
 
+- **Unconfigured models blocked** — models without a configured provider are filtered from selection surfaces, preventing dispatch failures.
+- **Provider readiness required** — saved default model selection now verifies the provider is ready before accepting it.
+- **Session override honored** — `/gsd model` selection persists as a session override across all dispatch phases.
+- **Minimal context guard** — model override logic is skipped in minimal command contexts where it doesn't apply.
+
+### Auto-Mode Resilience
+
+- **Credential cooldown recovery** — auto-mode survives transient 429 rate-limit responses with structured cooldown errors and a bounded retry budget.
+- **Fire-and-forget auto start** — auto start is detached from active turns to prevent blocking.
+- **Scoped forensics** — stuck-loop forensics are now scoped to auto sessions only, preventing false positives in interactive use.
+
+### TUI Improvements
+
+- **Overlay subscription fix** — resolved overlay subscription lifecycle and `Ctrl+Shift+P` shortcut conflict.
+- **Improved overlays and shortcuts** — GSD overlays, keyboard shortcuts, and notification flows redesigned for consistency.
 - **Pinned output restored** — pinned output bar displays above the editor during tool execution again.
 - **Turn completion cleanup** — pinned latest output is cleared on turn completion, preventing stale output from persisting.
 - **Secure input masking** — extension input values are masked in interactive mode when collecting secrets.
 
+### Provider Fixes
+
+- **Full OAuth login URLs** — OAuth login URLs are now displayed in full instead of being truncated.
+- **MiniMax bearer auth** — MiniMax Anthropic API requests use proper bearer authentication.
+- **Case-insensitive tool rendering** — renderable tool matching is now case-insensitive, fixing missed tool output.
+- **Headless idle timeout** — idle timeout is kept off during interactive tool execution in headless mode.
+
 ### Reliability & Internals
 
 - **TOCTOU file locking** — race conditions in event log and custom workflow graph file locking are fixed with proper atomic lock acquisition.
@@ -54,6 +76,9 @@ One command. Walk away. Come back to a built project with clean git history.
 - **Model routing transparency** — dynamic routing is skipped for interactive dispatches; model changes are always shown in the banner.
 - **Capability-aware routing (ADR-004)** — full implementation of capability scoring, `before_model_select` hook, and task metadata extraction.
 - **Multi-model provider strategy (ADR-005)** — infrastructure for multi-provider model selection wired into live paths.
+- **Anti-fabrication guardrails** — discuss prompts enforce turn-taking to prevent fabricated user responses.
+- **Milestone worktree cleanup** — merged worktree cleanup uses the milestone branch instead of generic lookups.
+- **Tool cache control** — `cache_control` breakpoints added to tool definitions for improved prompt caching.
 
 See the full [Changelog](./CHANGELOG.md) for details on every release.
 
@@ -732,6 +757,14 @@ Use expensive models where quality matters (planning, complex execution) and che
 
 ---
 
+## Ecosystem
+
+| Project | Description |
+| ------- | ----------- |
+| [GSD2 Config Utility](https://github.com/jeremymcs/gsd2-config) | Standalone configuration tool for managing GSD preferences, providers, and API keys |
+
+---
+
 ## Star History
 
 <a href="https://star-history.com/#gsd-build/gsd-2&Date">