agent: lumotia-rebrand — rust workspace crates magnotia-* -> lumotia-*

Phase 2 of the rebrand cascade. Renames all 9 workspace crates from
magnotia-* to lumotia-* plus the src-tauri binary crate name:

- magnotia-ai-formatting   -> lumotia-ai-formatting
- magnotia-audio           -> lumotia-audio
- magnotia-cloud-providers -> lumotia-cloud-providers
- magnotia-core            -> lumotia-core
- magnotia-hotkey          -> lumotia-hotkey
- magnotia-llm             -> lumotia-llm
- magnotia-mcp             -> lumotia-mcp
- magnotia-storage         -> lumotia-storage
- magnotia-transcription   -> lumotia-transcription
- magnotia                 -> lumotia (src-tauri binary)
- magnotia_lib             -> lumotia_lib (src-tauri lib target)

Crate directories (crates/audio/ etc.) stay as-is; only the Cargo.toml
[package] name field changes plus all consumer module imports
(magnotia_core -> lumotia_core, etc.).

Remaining magnotia_* references at this point are intentional and
scoped to later phases: tracing targets (Phase 4), DB setting keys
magnotia_preferences/magnotia_history (Phase 5).

cargo build --workspace passes. cargo test --workspace: 330 pass, 0 fail.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/audio/src/concurrency.rs

@@ -1,7 +1,7 @@
 use std::path::Path;
 
-use magnotia_core::error::Result;
-use magnotia_core::types::AudioSamples;
+use lumotia_core::error::Result;
+use lumotia_core::types::AudioSamples;
 
 use crate::decode::decode_audio_file;
 use crate::resample::resample_to_16khz;
@@ -16,6 +16,6 @@ pub async fn decode_and_resample(path: &Path) -> Result<AudioSamples> {
     })
     .await
     .map_err(|e| {
-        magnotia_core::error::MagnotiaError::AudioDecodeFailed(format!("Task join error: {e}"))
+        lumotia_core::error::MagnotiaError::AudioDecodeFailed(format!("Task join error: {e}"))
     })?
 }