fix(session-analysis): recognize lowercase edit tool names from Pi sessions

Pi's coding agent emits lowercase tool names (edit, write), while the
edit-event detection in episode-contract and insights matched Claude
Code's capitalized names (Edit, Write) with a case-sensitive Set lookup.
Every Pi edit event was therefore missed, which surfaced as
withChanges: 0 in session facts for any workspace with real commits.

Store the edit tool names lowercase and compare against the lowercased
tool name, matching the existing case-insensitive check used for
PATHLESS_EDIT_TOOL_NAMES in the same function.

Validation: reran session-analysis facts --platform pi over a 254-session
workspace; populationCoverage.withChanges moved 0 -> 29, candidate
classes gained change-gap 11, and read-only-work dropped 44 -> 21 as
editing episodes were no longer misclassified. The existing episode
contract and lifecycle signal tests (28 tests, all using capitalized
Claude tool names) pass unchanged, confirming backward compatibility.

Author: wangchen01

scripts/session-analysis/episode-contract.mjs

@@ -11,13 +11,16 @@ export const EVENT_SCHEMA_VERSION = 2;
 export const TASK_EPISODE_SCHEMA_VERSION = 3;
 export const DEFAULT_EPISODE_GAP_MS = 30 * 60 * 1000;
 
+// Tool-name matching is case-insensitive: providers differ in casing
+// (Claude Code emits "Edit"/"Write", pi emits "edit"/"write"), so entries
+// are stored lowercase and compared against the lowercased tool name.
 const EDIT_TOOL_NAMES = new Set([
-  "Edit",
-  "MultiEdit",
-  "NotebookEdit",
-  "NotebookWrite",
-  "SearchReplace",
-  "Write",
+  "edit",
+  "multiedit",
+  "notebookedit",
+  "notebookwrite",
+  "searchreplace",
+  "write",
 ]);
 const PATHLESS_EDIT_TOOL_NAMES = new Set(["apply_patch"]);
 const LIFECYCLE_USER_EVENT_TYPES = new Set(["user", "last-prompt", "UserPromptSubmit"]);
@@ -131,7 +134,7 @@ export function isEditEvent(event) {
   if (event?.type === "event.patch_apply_end") return true;
   if (PATHLESS_EDIT_TOOL_NAMES.has(String(event?.toolName ?? event?.functionCallName ?? "").toLowerCase())) return true;
   if (/^\s*apply_patch(?:\s|$)/u.test(String(event?.commandText ?? ""))) return true;
-  return targetPaths.length > 0 && EDIT_TOOL_NAMES.has(event?.toolName);
+  return targetPaths.length > 0 && EDIT_TOOL_NAMES.has(String(event?.toolName ?? "").toLowerCase());
 }
 
 export function validationCategory(event) {

scripts/session-analysis/insights.mjs

@@ -31,7 +31,8 @@ const FRICTION_TYPE_PATTERNS = Object.freeze([
   { name: "aborted-event", pattern: /\b(?:abort|aborted|cancel|cancelled|interrupted)\b/i },
 ]);
 
-const EDIT_TOOL_NAMES = new Set(["Edit", "MultiEdit", "NotebookEdit", "Write"]);
+// Case-insensitive: providers differ in casing (Claude Code "Edit", pi "edit").
+const EDIT_TOOL_NAMES = new Set(["edit", "multiedit", "notebookedit", "write"]);
 
 const EDIT_COMMAND_PATTERNS = Object.freeze([
   { name: "apply_patch", pattern: /\bapply_patch\b|\*\*\*\s+Begin Patch/i },
@@ -724,7 +725,7 @@ function longSessionRows(rows = []) {
 }
 
 function isEditEvent(event) {
-  if (EDIT_TOOL_NAMES.has(event.toolName)) {
+  if (EDIT_TOOL_NAMES.has(String(event?.toolName ?? "").toLowerCase())) {
     return true;
   }
   const commandText = event.commandText ?? "";