feat: add AWS Bedrock LLM provider via native Converse API (#713)

* feat: add AWS Bedrock LLM provider via native Converse API

* fix: use JSON parsing for tool result error detection instead of brittle substring matching

* refactor: extract duplicated inference config builder into helper function

* fix: address review feedback — safe casts, input validation, and tests

- Safe u32→i32 cast for max_tokens using try_from with clamp
- Remove brittle string-based error detection fallback for tool results
- Validate BEDROCK_CROSS_REGION against allowed values (us/eu/apac/global)
- Validate message list is non-empty before Converse API call
- Log when using default us-east-1 region
- Update llm_backend doc comment to list all backends
- Add tests for build_inference_config and empty message handling

* fix: persist AWS_PROFILE for Bedrock named profile auth

The wizard collected the profile name but only printed a hint to set
it manually. Now it saves to settings and writes AWS_PROFILE to the
bootstrap .env, consistent with how BEDROCK_REGION and other Bedrock
settings are persisted.

* feat: gate AWS Bedrock behind optional `bedrock` feature flag

The AWS SDK dependencies (aws-config, aws-sdk-bedrockruntime,
aws-smithy-types) require cmake and a C compiler to build aws-lc-sys.
Gate them behind an opt-in `bedrock` feature flag so default builds
are unaffected.

Build with: cargo build --features bedrock
All config, settings, and wizard code stays unconditional (no AWS deps)
so users can configure Bedrock even without the feature compiled — they
get a clear error at startup directing them to rebuild.

* fix: address review feedback and adapt Bedrock provider to registry architecture (takeover #345)

- Resolve merge conflicts with main's registry-based provider system
- Add missing cache_creation_input_tokens/cache_read_input_tokens fields
- Add missing content_parts field in test ChatMessage
- Fix string literal type mismatches in wizard env_vars (.to_string())
- Remove non-functional bearer token auth (AWS_BEARER_TOKEN_BEDROCK) from
  wizard and documentation per reviewer feedback from @zmanian and @serrrfirat
- Remove stale BEDROCK_ACCESS_KEY proxy entry from provider table
- Update Bedrock provider to use is_bedrock string check (LlmBackend enum removed)
- Add bedrock_profile fallback from settings in config resolution

[skip-regression-check]

Co-Authored-By: cgorski <[email protected]>
Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix: use main's Cargo.lock as base to preserve dependency versions

Regenerating Cargo.lock from scratch caused transitive dependency version
drift that broke the html_to_markdown fixture test in CI.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix: bedrock config bugs — spurious warning, alias normalization, profile fallback

- Move is_bedrock check before unknown-backend warning to prevent
  spurious "unknown backend" log for bedrock users
- Normalize backend aliases ("aws", "aws_bedrock") to "bedrock" so
  the provider factory matches correctly
- Add settings.bedrock_profile fallback for AWS_PROFILE, consistent
  with region and cross_region resolution

[skip-regression-check]

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix: address Copilot review feedback — bearer token cleanup, stop_sequences, model dedup

- Remove stale bearer token refs from setup README and CHANGELOG
- Remove dead bedrock_api_key secret injection mapping
- Pass stop_sequences through to Bedrock InferenceConfiguration
- Remove "API key" from wizard menu description (bearer token removed)
- Skip duplicate LLM_MODEL write for bedrock backend in wizard
- Fix cargo fmt formatting

[skip-regression-check]

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix: address review feedback — async new(), remove LiteLLM entry, wizard fixes

- Remove dead LiteLLM-based bedrock entry from providers.json (native
  Converse API intercepts before registry lookup)
- Make BedrockProvider::new() async to avoid block_in_place panic in
  current_thread runtimes; propagate async to create_llm_provider,
  build_provider_chain, and init_llm
- Document CMake build prerequisite in docs/LLM_PROVIDERS.md
- Clear bedrock_profile when user selects "default credentials" in wizard
- Fix selected_model clearing to match established pattern (conditional
  on provider switch, not unconditional)
- Add regression tests for bedrock model preservation and profile clearing

Addresses review feedback from @zmanian on PR #713.
Streaming support tracked in #741.

[skip-regression-check]

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix: address remaining review comments — CLAUDE.md backends, wizard UX

- Add `bedrock` to CLAUDE.md inline backend list (#10)
- Skip full setup re-run when keeping existing Bedrock config (#11)
- Clear stale bedrock_profile on empty named-profile input (#12)
- Add regression test for empty profile clearing

Co-Authored-By: Claude Opus 4.6 <[email protected]>

---------

Co-authored-by: Chris Gorski <[email protected]>
Co-authored-by: cgorski <[email protected]>
Co-authored-by: Claude Opus 4.6 <[email protected]>

docs/LLM_PROVIDERS.md

@@ -12,12 +12,12 @@ configurations.
 | Anthropic | `anthropic` | `ANTHROPIC_API_KEY` | Claude models |
 | OpenAI | `openai` | `OPENAI_API_KEY` | GPT models |
 | Google Gemini | `gemini` | `GEMINI_API_KEY` | Gemini models |
-| AWS Bedrock | `bedrock` | `BEDROCK_ACCESS_KEY` | Requires OpenAI proxy (e.g. LiteLLM) |
 | io.net | `ionet` | `IONET_API_KEY` | Intelligence API |
 | Mistral | `mistral` | `MISTRAL_API_KEY` | Mistral models |
 | Yandex AI Studio | `yandex` | `YANDEX_API_KEY` | YandexGPT models |
 | Cloudflare Workers AI | `cloudflare` | `CLOUDFLARE_API_KEY` | Access to Workers AI |
 | Ollama | `ollama` | No | Local inference |
+| AWS Bedrock | `bedrock` | AWS credentials | Native Converse API |
 | OpenRouter | `openai_compatible` | `LLM_API_KEY` | 300+ models |
 | Together AI | `openai_compatible` | `LLM_API_KEY` | Fast inference |
 | Fireworks AI | `openai_compatible` | `LLM_API_KEY` | Fast inference |
@@ -74,6 +74,55 @@ Pull a model first: `ollama pull llama3.2`
 
 ---
 
+## AWS Bedrock (requires `--features bedrock`)
+
+Uses the native AWS Converse API via `aws-sdk-bedrockruntime`. Supports standard AWS
+authentication methods: IAM credentials, SSO profiles, and instance roles.
+
+> **Build prerequisite:** The `aws-lc-sys` crate (transitive dependency via AWS SDK)
+> requires **CMake** to compile. Install it before building with `--features bedrock`:
+> - macOS: `brew install cmake`
+> - Ubuntu/Debian: `sudo apt install cmake`
+> - Fedora: `sudo dnf install cmake`
+
+### With AWS credentials (IAM, SSO, instance roles)
+
+```env
+LLM_BACKEND=bedrock
+BEDROCK_MODEL=anthropic.claude-opus-4-6-v1
+BEDROCK_REGION=us-east-1
+BEDROCK_CROSS_REGION=us
+# AWS_PROFILE=my-sso-profile   # optional, for named profiles
+```
+
+The AWS SDK credential chain automatically resolves credentials from environment
+variables (`AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`), shared credentials file
+(`~/.aws/credentials`), SSO profiles, and EC2/ECS instance roles.
+
+### Cross-region inference
+
+Set `BEDROCK_CROSS_REGION` to route requests across AWS regions for capacity:
+
+| Prefix | Routing |
+|---|---|
+| `us` | US regions (us-east-1, us-east-2, us-west-2) |
+| `eu` | European regions |
+| `apac` | Asia-Pacific regions |
+| `global` | All commercial AWS regions |
+| _(unset)_ | Single-region only |
+
+### Popular Bedrock model IDs
+
+| Model | ID |
+|---|---|
+| Claude Opus 4.6 | `anthropic.claude-opus-4-6-v1` |
+| Claude Sonnet 4.5 | `anthropic.claude-sonnet-4-5-20250929-v1:0` |
+| Claude Haiku 4.5 | `anthropic.claude-haiku-4-5-20251001-v1:0` |
+| Amazon Nova Pro | `amazon.nova-pro-v1:0` |
+| Llama 4 Maverick | `meta.llama4-maverick-17b-instruct-v1:0` |
+
+---
+
 ## OpenAI-Compatible Endpoints
 
 All providers below use `LLM_BACKEND=openai_compatible`. Set `LLM_BASE_URL` to the