deps: bump go-llm-sdk to v0.3.3 and drop the local workspace overlay (#239)

* deps: bump go-llm-sdk to v0.3.3 and drop the local workspace overlay

v0.3.3 carries the DeepSeek thinking-mode fix: an empty reasoning_content
is echoed on requests that carry tools, so a turn whose reasoning the
provider elided no longer serializes without the key and no longer kills
the rest of the tool loop with a 400.

Bumping to the released module lets the local go.work overlay go away
entirely, so every build resolves the same code: local dev, CI and release.
The overlay existed only to develop the fix in place; now that it is
released it is pure drift risk, because it made local binaries run
unreleased code while CI and releases ran the pinned tag.

Verified with no workspace present (GOWORK unset):
  go list -m github.com/BackendStack21/go-llm-sdk -> v0.3.3
  go build ./...                                  ok
  go test ./internal/llmclient/... ./internal/loop/... ./internal/session/...  ok
  go test -race ./internal/llmclient/...          ok

go.mod: one line. go.sum: two. No other dependency movement.

* docs: document the DeepSeek reasoning-replay requirement and the v0.3.3 floor

The dependency bump alone leaves the contract undocumented: PROVIDERS.md
described the GPT-5.6 tools+reasoning route but said nothing about DeepSeek's
reasoning_content replay rule, which is what breaks long tool loops on the
older SDK. MIGRATION.md pinned "go-llm-sdk v0.3.2+" as the recommended floor.

- PROVIDERS.md: a DeepSeek paragraph next to the GPT-5.6 one, stating that
  reasoning_content is required on every assistant turn of a tool-carrying
  request (including turns where the provider returned no reasoning), that
  v0.3.3+ echoes the key, and that v0.3.2 and older die mid-loop with the
  reported 400.
- MIGRATION.md: the recommended pin moves to v0.3.3+ with the DeepSeek reason
  added alongside the existing GPT-5.6 and cache reasons.

Docs only, no behaviour change.

Author: jkyberneees

docs/MIGRATION.md

@@ -149,4 +149,4 @@ agent, err := odek.New(odek.Config{
 
 ## Cache / cost budgets
 
-Cache usage fields come from the SDK (`Usage.Cache*`). Pin **go-llm-sdk v0.3.2+** so GPT-5.6 tools+reasoning stays on (`POST /v1/responses`) and cache-token parsing remains honest.
+Cache usage fields come from the SDK (`Usage.Cache*`). Pin **go-llm-sdk v0.3.3+** so GPT-5.6 tools+reasoning stays on (`POST /v1/responses`), cache-token parsing remains honest, and DeepSeek thinking-mode tool loops replay `reasoning_content` instead of dropping it (v0.3.2 and older lose the key on turns where the provider elided reasoning, and the loop 400s from then on).

docs/PROVIDERS.md

@@ -47,6 +47,15 @@ actually reasons, and a reasoning summary is streamed back. `thinking=disabled`
 stays on Chat Completions with `reasoning_effort: none`. The same Responses
 route is used for GPT-5.4/5.5 when an explicit thinking level is set.
 
+**DeepSeek (`deepseek`, the default id):** thinking mode requires
+`reasoning_content` to be replayed on every assistant turn of a request that
+carries tools, including turns where the provider returned no reasoning of
+its own, which happens on some turns. With go-llm-sdk v0.3.3+ odek echoes the
+key on tool-carrying requests, so such a turn no longer serializes without it.
+On v0.3.2 and older the key is dropped when empty and a long tool loop dies
+mid-run with `400 ... The reasoning_content in the thinking mode must be
+passed back to the API`, then fails on every later request in that loop.
+
 ## odek knobs (not in the SDK)
 
 | Knob | Where |

go.mod

@@ -11,4 +11,4 @@ require (
 
 require golang.org/x/sys v0.47.0
 
-require github.com/BackendStack21/go-llm-sdk v0.3.2
+require github.com/BackendStack21/go-llm-sdk v0.3.3

go.sum

@@ -1,5 +1,7 @@
 github.com/BackendStack21/go-llm-sdk v0.3.2 h1:aUXa450t+eOtLmuNX6gOMSD4zZsGCKtaIaG1YDHmNxY=
 github.com/BackendStack21/go-llm-sdk v0.3.2/go.mod h1:Nhro6plQaVIIFajPhzp2dzz4rv4DFU/yXNEudChllyE=
+github.com/BackendStack21/go-llm-sdk v0.3.3 h1:JlMQL8K7W+BVe7zjhP7MMYK5VNqmK38QlDrFjA7Pp2c=
+github.com/BackendStack21/go-llm-sdk v0.3.3/go.mod h1:Nhro6plQaVIIFajPhzp2dzz4rv4DFU/yXNEudChllyE=
 github.com/BackendStack21/go-mcp v1.3.0 h1:55iJgiAgcptv+mQwWEHNaFqPJksPR6zn4beYjHk/Ea4=
 github.com/BackendStack21/go-mcp v1.3.0/go.mod h1:RKFw6nrl6ySQqqrR8KtG7HYZ/heyyjT8SjiEtlbTMY8=
 github.com/BackendStack21/go-vector v1.4.0 h1:Ssu5RDEt4Cr9A17/ogdfjeuaLFFNHASJBIEGpqKzAV0=