feat: DSML tool-call recovery plugin for OpenCode V2

Recovers DeepSeek DSML tool calls that leak as assistant text: streaming
middleware (AI-SDK path), SSE rewrite (native path), history sanitization,
preventive directive, conditional system nudge, and a capped idle watchdog.
116 tests, synthetic golden fixtures.

tsconfig.json

@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "lib": ["ESNext"],
+    "types": ["bun-types"],
+    "strict": true,
+    "noUncheckedIndexedAccess": true,
+    "noEmit": true,
+    "skipLibCheck": true,
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "resolveJsonModule": true
+  },
+  "include": ["src", "test"]
+}