session: add TranscriptInfo struct, consolidate transcript lookups

TranscriptInfo provides cached transcript metadata (path, size)
with a single read. Replaces scattered fs::metadata calls in
surface_observe_cycle, reflection_cycle, resolve_conversation,
and resolve_memory_ratio.

Session::transcript() resolves the path from transcript_path or
by searching projects dir, returning a TranscriptInfo.

Co-Authored-By: Kent Overstreet <kent.overstreet@linux.dev>

src/hippocampus/memory_search.rs

@@ -10,7 +10,7 @@ use std::fs::File;
 use std::io::Write;
 use std::path::Path;
 use std::process::Command;
-use std::time::{Duration, SystemTime};
+use std::time::{Duration, Instant, SystemTime};
 
 
 /// Max bytes per context chunk (hook output limit is ~10K chars)
@@ -188,9 +188,8 @@ fn surface_observe_cycle(session: &Session, out: &mut String, log_f: &mut File)
     // (studying, reading a book, etc.)
     let conversation_budget: u64 = 50_000;
     let offset_path = state_dir.join("transcript-offset");
-    let transcript_size = if !session.transcript_path.is_empty() {
-        fs::metadata(&session.transcript_path).map(|m| m.len()).unwrap_or(0)
-    } else { 0 };
+    let transcript = session.transcript();
+    let transcript_size = transcript.size;
 
     if !live.is_empty() && transcript_size > 0 {
         let last_offset: u64 = fs::read_to_string(&offset_path).ok()
@@ -199,14 +198,20 @@ fn surface_observe_cycle(session: &Session, out: &mut String, log_f: &mut File)
         let behind = transcript_size.saturating_sub(last_offset);
 
         if behind > conversation_budget / 2 {
-            let _ = writeln!(log_f, "agent {}KB behind (budget {}KB), waiting for catchup",
-                behind / 1024, conversation_budget / 1024);
             // Wait up to 30s for the current agent to finish
+            let sleep_start = Instant::now();
+
             for _ in 0..30 {
                 std::thread::sleep(std::time::Duration::from_secs(1));
                 let still_live = crate::agents::knowledge::scan_pid_files(&state_dir, timeout);
                 if still_live.is_empty() { break; }
             }
+
+            let sleep_duration = (Instant::now() - sleep_start).as_secs();
+
+            let _ = writeln!(log_f, "agent {}KB behind (budget {}KB), slept for {sleep_duration} seconds",
+                behind / 1024, conversation_budget / 1024);
+            out.push_str(&format!("Slept for {sleep_duration} seconds to let observe catch up\n"));
         }
     }
 
@@ -240,9 +245,8 @@ fn reflection_cycle(session: &Session, out: &mut String, log_f: &mut File) {
 
     // Check transcript growth since last reflection
     let offset_path = state_dir.join("transcript-offset");
-    let transcript_size = if !session.transcript_path.is_empty() {
-        fs::metadata(&session.transcript_path).map(|m| m.len()).unwrap_or(0)
-    } else { 0 };
+    let transcript = session.transcript();
+    let transcript_size = transcript.size;
 
     let last_offset: u64 = fs::read_to_string(&offset_path).ok()
         .and_then(|s| s.trim().parse().ok())

src/session.rs

@@ -1,7 +1,10 @@
-// session.rs — Session state for ambient hooks and agent interactions
+// session.rs — Session state and transcript info
 //
-// Tracks per-session state (seen set, state directory) across hook
+// Session: per-session state (seen set, state directory) across hook
 // invocations. Created from hook JSON input or POC_SESSION_ID env var.
+//
+// TranscriptInfo: cached metadata about the current session's transcript
+// file — size, path, compaction offset. Read once, used by all callers.
 
 use std::collections::HashSet;
 use std::fs;
@@ -53,4 +56,51 @@ impl Session {
     pub fn seen(&self) -> HashSet<String> {
         super::hippocampus::memory_search::load_seen(&self.state_dir, &self.session_id)
     }
+
+    /// Get transcript metadata, resolving the path if needed.
+    pub fn transcript(&self) -> TranscriptInfo {
+        if !self.transcript_path.is_empty() {
+            return TranscriptInfo::from_path(&self.transcript_path);
+        }
+
+        // Find transcript by session ID in projects dir
+        let projects = crate::config::get().projects_dir.clone();
+        if let Ok(dirs) = fs::read_dir(&projects) {
+            for dir in dirs.filter_map(|e| e.ok()) {
+                let path = dir.path().join(format!("{}.jsonl", self.session_id));
+                if path.exists() {
+                    return TranscriptInfo::from_path(&path.to_string_lossy());
+                }
+            }
+        }
+
+        TranscriptInfo::empty()
+    }
+}
+
+/// Cached transcript metadata — read once, use everywhere.
+pub struct TranscriptInfo {
+    pub path: String,
+    pub size: u64,
+}
+
+impl TranscriptInfo {
+    pub fn from_path(path: &str) -> Self {
+        let size = fs::metadata(path).map(|m| m.len()).unwrap_or(0);
+        TranscriptInfo {
+            path: path.to_string(),
+            size,
+        }
+    }
+
+    pub fn empty() -> Self {
+        TranscriptInfo {
+            path: String::new(),
+            size: 0,
+        }
+    }
+
+    pub fn exists(&self) -> bool {
+        !self.path.is_empty() && self.size > 0
+    }
 }

src/subconscious/defs.rs

@@ -572,26 +572,14 @@ fn resolve(
 /// Reads POC_SESSION_ID to find the transcript, extracts the last
 /// segment (post-compaction), returns the tail (~100K chars).
 fn resolve_conversation(budget: Option<usize>) -> String {
-    let session_id = std::env::var("POC_SESSION_ID").unwrap_or_default();
-    if session_id.is_empty() { return String::new(); }
+    let session = crate::session::Session::from_env();
+    let transcript = session.as_ref()
+        .map(|s| s.transcript())
+        .unwrap_or_else(crate::session::TranscriptInfo::empty);
 
-    let projects = crate::config::get().projects_dir.clone();
-    // Find the transcript file matching this session
-    let mut transcript = None;
-    if let Ok(dirs) = std::fs::read_dir(&projects) {
-        for dir in dirs.filter_map(|e| e.ok()) {
-            let path = dir.path().join(format!("{}.jsonl", session_id));
-            if path.exists() {
-                transcript = Some(path);
-                break;
-            }
-        }
-    }
+    if !transcript.exists() { return String::new(); }
 
-    let Some(path) = transcript else { return String::new() };
-    let path_str = path.to_string_lossy();
-
-    let Some(iter) = crate::transcript::TailMessages::open(&path_str) else {
+    let Some(iter) = crate::transcript::TailMessages::open(&transcript.path) else {
         return String::new();
     };
 
@@ -680,22 +668,14 @@ fn resolve_memory_ratio() -> String {
     let state_dir = std::path::PathBuf::from("/tmp/claude-memory-search");
 
     // Get post-compaction transcript size
-    let projects = crate::config::get().projects_dir.clone();
-    let transcript_size: u64 = std::fs::read_dir(&projects).ok()
-        .and_then(|dirs| {
-            for dir in dirs.filter_map(|e| e.ok()) {
-                let path = dir.path().join(format!("{}.jsonl", session_id));
-                if path.exists() {
-                    let file_len = path.metadata().map(|m| m.len()).unwrap_or(0);
-                    let compaction_offset: u64 = std::fs::read_to_string(
-                        state_dir.join(format!("compaction-{}", session_id))
-                    ).ok().and_then(|s| s.trim().parse().ok()).unwrap_or(0);
-                    return Some(file_len.saturating_sub(compaction_offset));
-                }
-            }
-            None
-        })
-        .unwrap_or(0);
+    let session = crate::session::Session::from_env();
+    let transcript = session.as_ref()
+        .map(|s| s.transcript())
+        .unwrap_or_else(crate::session::TranscriptInfo::empty);
+    let compaction_offset: u64 = std::fs::read_to_string(
+        state_dir.join(format!("compaction-{}", session_id))
+    ).ok().and_then(|s| s.trim().parse().ok()).unwrap_or(0);
+    let transcript_size = transcript.size.saturating_sub(compaction_offset);
 
     if transcript_size == 0 {
         return "0% of context is recalled memories (new session)".to_string();