fix(plugin): harden metadata recovery and extraction

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/plugin/tool-execute-after.test.ts

@@ -1,7 +1,13 @@
-import { describe, expect, it } from "bun:test"
+import { beforeEach, describe, expect, it } from "bun:test"
+
+import { clearPendingStore, storeToolMetadata } from "../features/tool-metadata-store"
 import { createToolExecuteAfterHandler } from "./tool-execute-after"
 
 describe("createToolExecuteAfterHandler", () => {
+  beforeEach(() => {
+    clearPendingStore()
+  })
+
   it("#given truncator changes output #when tool.execute.after runs #then claudeCodeHooks receives truncated output", async () => {
     const callOrder: string[] = []
     let claudeSawOutput = ""
@@ -32,4 +38,58 @@ describe("createToolExecuteAfterHandler", () => {
     expect(callOrder).toEqual(["truncator", "claude"])
     expect(claudeSawOutput).toBe("truncated output")
   })
+
+  it("#given stored metadata with legacy call id casing #when tool.execute.after runs #then it restores the stored metadata", async () => {
+    // given
+    storeToolMetadata("ses_parent", "call_legacy", {
+      title: "stored title",
+      metadata: { sessionId: "ses_child", agent: "oracle" },
+    })
+
+    const handler = createToolExecuteAfterHandler({
+      ctx: { directory: "/repo" } as never,
+      hooks: {} as never,
+    })
+
+    const output = { title: "result", output: "original output", metadata: { truncated: true } }
+
+    // when
+    await handler(
+      { tool: "hashline_edit", sessionID: "ses_parent", callId: " call_legacy " },
+      output
+    )
+
+    // then
+    expect(output.title).toBe("stored title")
+    expect(output.metadata).toEqual({ truncated: true, sessionId: "ses_child", agent: "oracle" })
+  })
+
+  it("#given native session metadata #when stored metadata exists #then stored metadata does not overwrite native session linkage", async () => {
+    // given
+    storeToolMetadata("ses_parent", "call_native", {
+      title: "stored title",
+      metadata: { sessionId: "ses_stored", agent: "oracle" },
+    })
+
+    const handler = createToolExecuteAfterHandler({
+      ctx: { directory: "/repo" } as never,
+      hooks: {} as never,
+    })
+
+    const output = {
+      title: "result",
+      output: "original output",
+      metadata: { sessionId: "ses_native", agent: "hephaestus" },
+    }
+
+    // when
+    await handler(
+      { tool: "hashline_edit", sessionID: "ses_parent", callID: "call_native" },
+      output
+    )
+
+    // then
+    expect(output.title).toBe("stored title")
+    expect(output.metadata).toEqual({ sessionId: "ses_native", agent: "hephaestus" })
+  })
 })