chore(gomod): pin go directive to 1.25.0 (dep-mandated floor) + toolchain 1.25.7

Correction to the previous "pin to 1.25.7" commit. The `go` directive
in go.mod isn't a free choice — `go mod tidy` floors it at whatever the
highest-required transitive dependency declares. In our case:

    github.com/modelcontextprotocol/go-sdk v1.6.0 → go 1.25.0

So tidy rewrites the directive back to `go 1.25.0` if we set it lower
(verified: tried `go 1.22`, tidy refused).

Final shape:
  go 1.25.0        — module language minimum (dep-mandated)
  toolchain go1.25.7 — actual build toolchain (1.26+ not yet ubiquitous)

CI workflows (go-ci.yml + go-parity.yml) pin go-version: '1.25.7' to
match the toolchain line.

828 tests still pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: aksOps

go/go.mod

@@ -1,6 +1,16 @@
 module github.com/randomcodespace/codeiq/go
 
-go 1.25.7
+// Minimum Go version that can compile this module — clamped at 1.25.0
+// because github.com/modelcontextprotocol/go-sdk v1.6 (Phase 3, MCP
+// server) declares `go 1.25.0`. `go mod tidy` rewrites anything lower
+// back to 1.25.0. Bumping out of 1.25 should wait until a release of
+// that SDK that targets 1.26+.
+go 1.25.0
+
+// Actual build toolchain. Pinned to 1.25.7 — 1.26+ isn't on enough
+// developer machines yet. CI pins the same version (.github/workflows/
+// go-ci.yml + go-parity.yml).
+toolchain go1.25.7
 
 require github.com/mattn/go-sqlite3 v1.14.22