🔒 Fix potential memory exhaustion in socket reads (#59)

Addresses a security vulnerability where the daemon or client could be
forced to allocate up to 10MB of memory per malformed socket message,
potentially leading to Out-Of-Memory (OOM) crashes.

Changes:
- Introduced a central `MAX_MESSAGE_SIZE` constant of 128KB in `src/types/socket.rs`.
- Enforced the 128KB limit on incoming requests in `src/bin/daemon.rs`.
- Enforced the 128KB limit on incoming responses in `src/utils/daemon.rs`.
- Preserved detailed `eprintln!` logging when messages are rejected.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

src/bin/daemon.rs

@@ -1,5 +1,5 @@
 use pwsp::{
-    types::socket::{Request, Response},
+    types::socket::{Request, Response, MAX_MESSAGE_SIZE},
     utils::{
         commands::parse_command,
         daemon::{
@@ -109,7 +109,7 @@ async fn commands_loop(listener: UnixListener) -> Result<(), Box<dyn Error>> {
 
             let request_len = u32::from_le_bytes(len_bytes) as usize;
 
-            if request_len > 10 * 1024 * 1024 {
+            if request_len > MAX_MESSAGE_SIZE {
                 eprintln!(
                     "Failed to read message from client: request too large ({} bytes)!",
                     request_len