fix: conversation capture — catch any editNote error, fall through to create

The previous code matched specific error types (isNoteNotFoundError) to
decide whether to fall back to writeNote. The error format from callTool
didn't match, so writeNote never fired — zero conversations captured.

Fix: try append, if it fails for ANY reason, create the note. Also adds
Conversation schema frontmatter (type: Conversation, date) to created notes.

Fixes #22

Author: bm-clawd

bm-client.ts

@@ -855,22 +855,33 @@ export class BmClient {
       "---",
     ].join("\n")
 
+    // Try append first — if it fails for ANY reason, fall through to create
     try {
       await this.editNote(title, "append", entry)
       log.debug(`appended conversation to: ${title}`)
+      return
     } catch (err) {
-      if (!this.isNoteNotFoundError(err)) {
-        log.error("conversation append failed", err)
-        return
-      }
+      log.debug(`append failed, will create: ${getErrorMessage(err)}`)
+    }
 
-      const content = [`# Conversations ${dateStr}`, "", entry].join("\n")
-      try {
-        await this.writeNote(title, content, "conversations")
-        log.debug(`created conversation note: ${title}`)
-      } catch (createErr) {
-        log.error("conversation index failed", createErr)
-      }
+    // Create the note with frontmatter and first entry
+    const content = [
+      "---",
+      `title: Conversations ${dateStr}`,
+      "type: Conversation",
+      `date: "${dateStr}"`,
+      "---",
+      "",
+      `# Conversations ${dateStr}`,
+      "",
+      entry,
+    ].join("\n")
+
+    try {
+      await this.writeNote(title, content, "conversations")
+      log.debug(`created conversation note: ${title}`)
+    } catch (err) {
+      log.error("conversation index failed", err)
     }
   }