feat: replace custom memory MCP with Cognee remote server

- Remove memory_mcp.py (stdio markdown-file memory)
- Add Cognee MCP as remote Streamable HTTP toolset at 192.168.86.2:8003/mcp
- Filter to only remember/recall/forget tools via allowed_tools
- Update system prompt: Memory section moved to top priority with
  explicit 'call recall FIRST' instructions and examples
- Add COGNEE_MCP_URL env var to docker-compose
- Remove /memory volume mount (no longer needed)
- Rewrite memory tests to use Cognee HTTP client fixture
- 28/28 tests passing

agent/agent.py

@@ -38,7 +38,6 @@ GEMMA_MODEL = os.environ.get("GEMMA_MODEL", "gemma-4-e4b")
 GEMMA_API_KEY = os.environ.get("GEMMA_API_KEY", "not-needed")
 WEB_MCP_ENABLED = os.environ.get("WEB_MCP_ENABLED", "true").lower() in ("1", "true", "yes")
 FIRECRAWL_BASE = os.environ.get("FIRECRAWL_BASE", "http://192.168.86.2:3002")
-MEMORY_DIR = os.environ.get("MEMORY_DIR", "/memory")
 SKILLS_DIR = os.environ.get("SKILLS_DIR", "/skills")
 
 SYSTEM_PROMPT = textwrap.dedent("""\
@@ -63,6 +62,20 @@ SYSTEM_PROMPT = textwrap.dedent("""\
     - Never write more than three sentences in a row.
     - Never read back URLs, file paths, or technical identifiers.
 
+    # Memory (CRITICAL — ALWAYS call these tools directly, never dispatch)
+    When the user asks about personal information, past conversations, or
+    anything you might have stored, you MUST call recall FIRST before
+    answering. Do NOT say "I don't have that info" without calling recall.
+    When the user tells you something to remember or shares a preference,
+    you MUST call remember. Do NOT just say "okay I'll remember that."
+    - User says "what's my name?" → CALL recall with query="my name"
+    - User says "do you remember who I am?" → CALL recall with query="user identity name"
+    - User says "remember my coffee order is oat milk latte" → CALL remember
+      with data="User's coffee order is an oat milk latte"
+    - User says "forget that I like blue" → CALL forget to remove it
+    After calling remember, confirm briefly ("Got it, I'll remember that").
+    If recall returns nothing, then say you don't have that info yet.
+
     # Weather & Time
     You can check the weather for any location. Use get_weather when the user
     asks about current conditions, temperature, or forecasts. It returns a
@@ -72,38 +85,23 @@ SYSTEM_PROMPT = textwrap.dedent("""\
 
     # Background Tasks (dispatch_task) — USE FOR ALL NON-TRIVIAL TASKS
     For ANY task that is not a simple one-sentence answer from your own
-    knowledge, you MUST call dispatch_task. This includes: looking up news,
-    researching topics, checking current events, prices, sports scores,
-    writing something, summarizing, comparing options, planning, or anything
-    that takes more than a couple seconds to think through. Do NOT use
-    web_search or web_scrape directly; always dispatch instead.
-    The only things you answer inline are: weather (get_weather), time
-    (get_time), memory operations, and trivial facts you already know.
+    knowledge and NOT a memory operation, you MUST call dispatch_task.
+    This includes: looking up news, researching topics, checking current
+    events, prices, sports scores, writing something, summarizing, comparing
+    options, planning, or anything that takes more than a couple seconds to
+    think through. Do NOT use web_search or web_scrape directly; always
+    dispatch instead. Memory recall/remember is NEVER a dispatch task —
+    call those tools directly.
     Examples:
     - User says "what's the latest news?" → CALL dispatch_task with
       description="Find the top 5 international news headlines today"
     - User says "look up the price of a PS5" → CALL dispatch_task with
       description="Find the current retail price of a PlayStation 5"
-    - User says "plan a weekend trip to Denver" → CALL dispatch_task with
-      description="Plan a two-day weekend trip to Denver including activities"
     After calling dispatch_task, tell the user "I'll get on that for you"
     and keep the conversation going. The result comes back automatically — when
     you receive it, share the findings naturally in your conversational style.
     You can have multiple tasks running at once.
 
-    # Memory (CRITICAL — always use these tools)
-    You MUST call memory_save whenever the user tells you something to remember,
-    shares a preference, or says "remember that...". Do NOT just say "okay I'll
-    remember that" without actually calling the tool. Always call it.
-    - User says "remember my coffee order is oat milk latte" → CALL memory_save
-      with topic="coffee order", content="oat milk latte"
-    - User says "what did I tell you about my birthday?" → CALL memory_recall
-      with query="birthday"
-    - User says "list everything you remember about me" → CALL memory_list
-    After calling memory_save, confirm briefly ("Got it, I'll remember that")
-    but do NOT say "I saved it to my memory file" or similar.
-    If a recall returns nothing, just say you don't have that info yet.
-
     # Skills
     You have a skill library of learned procedures. Use skill_recall when you need
     to perform a task you've done before — it will give you the steps. When you
@@ -383,19 +381,19 @@ def build_mcp_toolsets() -> list[mcp.MCPToolset]:
     )
     logger.info("Weather MCP toolset enabled (wttr.in)")
 
-    memory_mcp_script = os.path.join(os.path.dirname(os.path.abspath(__file__)), "memory_mcp.py")
+    cognee_url = os.environ.get("COGNEE_MCP_URL", "http://192.168.86.2:8003/mcp")
     toolsets.append(
         mcp.MCPToolset(
             id="memory",
-            mcp_server=mcp.MCPServerStdio(
-                command=python_bin,
-                args=[memory_mcp_script],
-                env={**os.environ, "MEMORY_DIR": "/memory"},
-                client_session_timeout_seconds=30,
+            mcp_server=mcp.MCPServerHTTP(
+                url=cognee_url,
+                transport_type="streamable_http",
+                allowed_tools=["remember", "recall", "forget"],
+                client_session_timeout_seconds=60,
             ),
         )
     )
-    logger.info("Memory MCP toolset enabled (%s)", MEMORY_DIR)
+    logger.info("Memory MCP toolset enabled (Cognee at %s)", cognee_url)
 
     skills_mcp_script = os.path.join(os.path.dirname(os.path.abspath(__file__)), "skills_mcp.py")
     toolsets.append(