add configuration profiles with per-invocation --profile flag

- Add SystemPrompt field to HushConfig (empty = built-in default)
- Refactor ConfigManager: extract ApplyTomlFields, add LoadWithProfile(),
  ListProfiles(), GetProfilePath(), EnsureProfilesDirExists(); remove
  HUSH_PROFILE env-var logic (profiles are now resolved by the CLI)
- Extend socket protocol: action commands (START/STOP/TOGGLE/ABORT) now
  carry a [4-byte LE length][optional HushConfig JSON] payload so the CLI
  can pass a per-invocation config override without restarting the daemon
- Add GENERATE_PROFILE (cmd 7) socket command: CLI sends a description,
  daemon calls the LLM and returns a generated system prompt
- Orchestrator: StopAndProcessAsync accepts optional HushConfig override;
  ProcessWithLlmAsync uses proper system/user chat roles and respects
  config.SystemPrompt; add GenerateProfilePromptAsync
- Split CompleteTextAsync signature to (systemPrompt, userMessage, model)
  across ITextStreamingProvider, GroqProvider, FireworksProvider
- Add --profile/-p flag to hush toggle and hush stop
- Add hush profiles subcommand: list, get, new (manual or AI-generated), edit

Hush.Cli/src/Commands/StopCommand.cs

@@ -1,4 +1,5 @@
 using System.CommandLine;
+using Hush.Config;
 using Hush.Daemon;
 using Spectre.Console;
 
@@ -9,13 +10,28 @@ public static class StopCommand
     public static Command Create()
     {
         var command = new Command("stop", "Stop recording and process");
+
+        var profileOption = new Option<string?>(["--profile", "-p"], "Profile name to apply when processing");
+        command.AddOption(profileOption);
+
         command.SetHandler(async (context) =>
         {
+            var profileName = context.ParseResult.GetValueForOption(profileOption);
             try
             {
                 await using var client = new SocketClient();
                 await client.ConnectAsync(TimeSpan.FromSeconds(2));
-                await client.SendCommandAsync(DaemonProtocol.STOP);
+
+                if (!string.IsNullOrEmpty(profileName))
+                {
+                    var config = new ConfigManager().LoadWithProfile(profileName);
+                    await client.SendCommandWithConfigAsync(DaemonProtocol.STOP, config);
+                }
+                else
+                {
+                    await client.SendCommandAsync(DaemonProtocol.STOP);
+                }
+
                 AnsiConsole.MarkupLine("[green]Stop command sent[/]");
             }
             catch (Exception ex)