Add v0.2.0 features: vector search + tool permissions

- Local vector search: Ollama embeddings + semantic search
  - get-embedding with caching
  - cosine-similarity computation
  - semantic-search cognitive tool
  - :semantic-search tool for LLM queries

- Tool permission tiers: security gating for cognitive tools
  - Three tiers: :allow, :deny, :ask
  - Gate in execute-tool-action before tool runs
  - Defaults: :deny for shell/delete-file, :ask for eval/write-file
  - :tool-permissions cognitive tool for management

- Embedding provider support: Ollama AND llama.cpp
  - EMBEDDING_PROVIDER env var
  - EMBEDDING_MODEL env var
  - LLAMA_HOST for llama.cpp server

- .env.example: Add embedding config variables
- Fix parse-message in communication.lisp

- Update ASDF: add test files, tool-permissions skill

All 60 tests pass (6 suites x 100%)

library/communication.lisp

@@ -16,6 +16,13 @@
          (len (length msg-string)))
     (format nil "~6,'0x~a~%" len msg-string)))
 
+(defun parse-message (framed-string)
+  "Parses a hex-length prefixed framed string into a Lisp plist."
+  (let* ((len (parse-integer (subseq framed-string 0 6) :radix 16))
+         (payload (subseq framed-string 6 (+ 6 len))))
+    (let ((*read-eval* nil))
+      (read-from-string payload))))
+
 (defun read-framed-message (stream)
   "Reads a hex-length prefixed S-expression from the stream securely. Skips leading whitespace."
   (let ((length-buffer (make-string 6)))