Key crash reports the same way sessions are keyed

Reuse projectKeyFor/projectSessionsRoot instead of a second,
independently derived slug, so a crash report lands next to that
project's run.json and transcript rather than in a separate
directory. Also log when the crash-report write itself fails,
instead of exiting silently with no trace of the failure.

Author: TheGreatAxios

docs/IMPLEMENTATION.md

@@ -329,7 +329,7 @@ session; that tree re-write is inherent to git and left as residual cost.
 
 ### Crash Logging
 
-`index.ts` installs `uncaughtException` and `unhandledRejection` handlers (and catches a rejected `main`). Each writes a best-effort crash report to `~/.corbits/projects/<project-slug>/errors/<timestamp>.txt`, where the slug is the cwd with non-alphanumeric runs collapsed to `-`. The file records the failure kind, an ISO timestamp, the cwd, and the stack. The logger swallows its own errors so it can never mask the original crash, then exits non-zero after printing a one-line message to stderr.
+`index.ts` installs `uncaughtException` and `unhandledRejection` handlers (and catches a rejected `main`). Each writes a best-effort crash report to `~/.corbits/projects/<project-key>/errors/<timestamp>.txt`, using the same `projectKeyFor`/`projectSessionsRoot` (`session/project-key.ts`) that keys that project's session directories, so a crash report lands next to the session's `run.json` and transcript rather than under a separately computed slug. The file records the failure kind, an ISO timestamp, the cwd, and the stack. The writer swallows its own errors (logging a one-line failure notice to stderr instead) so it can never mask the original crash, then exits non-zero after printing a one-line message to stderr.
 
 ### Event Stream
 

src/crash/report.test.ts

@@ -3,6 +3,7 @@ import { mkdtemp, readFile, readdir, rm } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 
+import { projectSessionsRoot } from "../session/project-key.js";
 import { crashReportDir, writeCrashReport } from "./report.js";
 
 let home: string | undefined;
@@ -15,7 +16,14 @@ afterEach(async () => {
 });
 
 describe("writeCrashReport", () => {
-  test("writes a report under ~/.corbits/projects/<slug>/errors/", async () => {
+  test("keys the crash directory the same way as the session directory", () => {
+    home = undefined; // no filesystem needed for this one
+    const cwd = "/Users/dev/some project!!";
+    const tmpHome = "/tmp/corbits-crash-key-check";
+    expect(crashReportDir(cwd, tmpHome)).toBe(join(projectSessionsRoot(cwd, tmpHome), "errors"));
+  });
+
+  test("writes a report under ~/.corbits/projects/<project-key>/errors/", async () => {
     home = await mkdtemp(join(tmpdir(), "corbits-crash-"));
     const cwd = "/Users/dev/some project!!";
     const file = await writeCrashReport("uncaughtException", new Error("boom"), cwd, home);

src/crash/report.ts

@@ -2,20 +2,15 @@ import { mkdir, writeFile } from "node:fs/promises";
 import { homedir } from "node:os";
 import { join } from "node:path";
 
-import { SETTINGS_DIR_NAME } from "../branding.js";
+import { projectSessionsRoot } from "../session/project-key.js";
 
 export type CrashKind = "uncaughtException" | "unhandledRejection";
 
-// Deliberately independent of session/project-key.ts: a crash can happen
-// before config or git discovery ever runs, so this slug is just the raw cwd
-// with non-alphanumeric runs collapsed, not the hashed project key.
-function slugifyCwd(cwd: string): string {
-  const slug = cwd.replace(/[^a-zA-Z0-9]+/g, "-").replace(/^-+|-+$/g, "");
-  return slug.length > 0 ? slug : "project";
-}
-
+// Must share the same key as the session's own directory (projectSessionsRoot)
+// so a crash report lands next to that session's run.json and transcript
+// instead of in a second, differently-keyed tree.
 export function crashReportDir(cwd: string, home: string = homedir()): string {
-  return join(home, SETTINGS_DIR_NAME, "projects", slugifyCwd(cwd), "errors");
+  return join(projectSessionsRoot(cwd, home), "errors");
 }
 
 function describeError(error: unknown): string {

src/index.ts

@@ -106,6 +106,8 @@ async function handleFatal(kind: CrashKind, error: unknown): Promise<void> {
   const file = await writeCrashReport(kind, error);
   if (file !== null) {
     process.stderr.write(`crash report written to ${file}\n`);
+  } else {
+    process.stderr.write("failed to write crash report\n");
   }
   process.exit(1);
 }