Fix memlog Python floor and exclude tests from install

- memlog.py: add 'from __future__ import annotations' so PEP 585/604
  hints stay lazy; the script runs on Python 3.8+ instead of crashing
  below 3.10. Correct the requires-python header to >=3.8.
- installer.js: filter tests/, __pycache__/, .pytest_cache/, and *.pyc
  out of _installSharedScripts so dev-only files never ship to users.

src/scripts/memlog.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 # /// script
-# requires-python = ">=3.10"
+# requires-python = ">=3.8"
 # ///
 """memlog — an append-only memory log: LLM-optimal working memory for a skill.
 
@@ -66,6 +66,8 @@ Commands:
 Addressing: `--workspace` is the run folder, and the memlog is always {workspace}/.memlog.md.
 `--path` points straight at the memlog file instead, for callers that already hold the path.
 """
+from __future__ import annotations  # keep type-hint syntax lazy so the script runs on 3.8+
+
 import argparse
 import json
 import os

tools/installer/core/installer.js

@@ -630,6 +630,7 @@ class Installer {
   /**
    * Sync src/scripts/* → _bmad/scripts/ so shared Python scripts
    * (e.g. resolve_customization.py) are available at install time.
+   * Excludes dev-only tests and Python caches so they don't ship to users.
    * Wipes the destination first so files removed or renamed in source
    * don't linger and get recorded as installed. Also seeds
    * _bmad/custom/.gitignore on fresh installs so *.user.toml overrides
@@ -643,7 +644,12 @@ class Installer {
 
     await fs.remove(paths.scriptsDir);
     await fs.ensureDir(paths.scriptsDir);
-    await fs.copy(srcScriptsDir, paths.scriptsDir, { overwrite: true });
+    // Ship only the runtime scripts — dev-only tests and Python caches must not land in user projects.
+    const isInstallable = (srcPath) => {
+      const base = path.basename(srcPath);
+      return base !== 'tests' && base !== '__pycache__' && base !== '.pytest_cache' && !base.endsWith('.pyc');
+    };
+    await fs.copy(srcScriptsDir, paths.scriptsDir, { overwrite: true, filter: isInstallable });
     await this._trackFilesRecursive(paths.scriptsDir);
 
     const customGitignore = path.join(paths.customDir, '.gitignore');