Add terminal client, memory, model fallback, version and install improvements

- codecraft: full-screen terminal client (ratatui) – local tools and files,
  models via the CodeCraft server gateway or own providers (standalone with a
  guided setup), slash commands, @files, permission dialogs, resume, update
- Static Linux CLI builds (x86_64/aarch64, cargo-zigbuild) served by the
  server: /cli/install.sh and /cli/download/<target>
- Project memory (remember tool, .codecraft/memory.md) and personal memory
- Model fallback when a host is unreachable or a budget is used up
- Version/commit in UI and health, daily release check, "What's new" dialog
- PWA: install button, maskable icon, manifest id and screenshots
- Case-insensitive detection of connection errors for retries

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/src/tools/agent.rs

@@ -97,6 +97,45 @@ impl Tool for CraftPhase {
 
 // ---------------------------------------------------------------------------
 
+/// Project memory: lasting facts about the project in .codecraft/memory.md.
+pub struct Remember;
+
+#[async_trait]
+impl Tool for Remember {
+    fn name(&self) -> &str {
+        "remember"
+    }
+    fn description(&self) -> String {
+        "Save a lasting insight about this project (build/test commands, conventions, pitfalls, decisions) to \
+         .codecraft/memory.md – it is loaded into every future session in this project. Keep entries short; \
+         never store secrets or temporary state."
+            .into()
+    }
+    fn schema(&self) -> Value {
+        json!({"type": "object", "properties": {"note": {"type": "string"}}, "required": ["note"]})
+    }
+    fn is_edit(&self) -> bool {
+        true
+    }
+    fn title(&self, input: &Value) -> String {
+        input["note"].as_str().unwrap_or("").chars().take(80).collect()
+    }
+    async fn run(&self, input: Value, ctx: &ToolCtx) -> Result<ToolOutput> {
+        let note = arg_str(&input, "note")?.trim().replace('\n', " ");
+        let path = ctx.resolve(".codecraft/memory.md")?;
+        std::fs::create_dir_all(path.parent().unwrap())?;
+        let mut text = std::fs::read_to_string(&path).unwrap_or_else(|_| "# Project memory\n\nLearned facts about this project (maintained by CodeCraft; edit freely).\n\n".into());
+        if !text.ends_with('\n') {
+            text.push('\n');
+        }
+        text.push_str(&format!("- {note}\n"));
+        std::fs::write(&path, &text)?;
+        Ok(ToolOutput::text(format!("Saved to .codecraft/memory.md: {note}")).with_meta(json!({"memory": note})))
+    }
+}
+
+// ---------------------------------------------------------------------------
+
 /// Switch the session's working directory (only on the user's request).
 pub struct ChangeDirectory;
 

server/src/tools/mod.rs

@@ -164,6 +164,7 @@ pub fn builtin_tools() -> Vec<Arc<dyn Tool>> {
         Arc::new(web::WebSearch),
         Arc::new(agent::CraftPhase),
         Arc::new(agent::ChangeDirectory),
+        Arc::new(agent::Remember),
         Arc::new(cad::OpenScad),
         Arc::new(crate::jobs::Schedule),
         Arc::new(crate::lsp::Diagnostics),