agent: lumotia-rebrand — drop MagnotiaError prefix, now lumotia_core::Error

Phase 3 of the rebrand cascade per locked decision D4. MagnotiaError ->
Error in crates/core/src/error.rs (the crate name already qualifies it).
92 usages across 14 .rs files renamed via word-boundary sed.

One collision required disambiguation: lumotia_storage already had its
own local Error type (introduced by the slop-pass Area A residuals work).
crates/storage/src/error.rs aliases the imported core error as CoreError
on import; the From<Error> for CoreError boundary impl and the
CoreError::Storage construction site use the alias.

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/capture.rs

@@ -8,7 +8,7 @@ use regex::Regex;
 use serde::{Deserialize, Serialize};
 use std::sync::OnceLock;
 
-use lumotia_core::error::{MagnotiaError, Result};
+use lumotia_core::error::{Error, Result};
 
 const AUDIO_CHANNEL_CAPACITY: usize = 32;
 
@@ -106,7 +106,7 @@ impl MicrophoneCapture {
 
         let devices = host
             .input_devices()
-            .map_err(|e| MagnotiaError::AudioCaptureFailed(format!("input_devices: {e}")))?;
+            .map_err(|e| Error::AudioCaptureFailed(format!("input_devices: {e}")))?;
 
         // Load ALSA card descriptions once per enumeration. These are the
         // "real" product names (e.g. "Blue Microphones") that cpal's
@@ -144,7 +144,7 @@ impl MicrophoneCapture {
         let host = cpal::default_host();
         let devices = host
             .input_devices()
-            .map_err(|e| MagnotiaError::AudioCaptureFailed(format!("input_devices: {e}")))?;
+            .map_err(|e| Error::AudioCaptureFailed(format!("input_devices: {e}")))?;
 
         for device in devices {
             let name = device_display_name(&device).unwrap_or_default();
@@ -154,7 +154,7 @@ impl MicrophoneCapture {
             }
         }
 
-        Err(MagnotiaError::AudioCaptureFailed(format!(
+        Err(Error::AudioCaptureFailed(format!(
             "Selected device '{device_name}' not found in current host enumeration. \
              It may have been disconnected. Open Settings → Audio to pick another."
         )))
@@ -178,7 +178,7 @@ impl MicrophoneCapture {
 
         let mut all_devices: Vec<cpal::Device> = host
             .input_devices()
-            .map_err(|e| MagnotiaError::AudioCaptureFailed(format!("input_devices: {e}")))?
+            .map_err(|e| Error::AudioCaptureFailed(format!("input_devices: {e}")))?
             .collect();
 
         // Sort: default first, then non-monitor, then monitor-as-last-resort.
@@ -237,7 +237,7 @@ impl MicrophoneCapture {
             }
         }
 
-        Err(MagnotiaError::AudioCaptureFailed(
+        Err(Error::AudioCaptureFailed(
             "No working microphone found. Check that an input device is connected, \
              that PulseAudio/PipeWire is running, and that the app has microphone permission. \
              Then open Settings → Audio to pick a device explicitly."
@@ -361,7 +361,7 @@ fn open_and_validate(
 ) -> Result<(MicrophoneCapture, mpsc::Receiver<AudioChunk>)> {
     let config = device
         .default_input_config()
-        .map_err(|e| MagnotiaError::AudioCaptureFailed(format!("default_input_config: {e}")))?;
+        .map_err(|e| Error::AudioCaptureFailed(format!("default_input_config: {e}")))?;
     let sample_rate = config.sample_rate();
     let channels = config.channels();
     let format = config.sample_format();
@@ -422,16 +422,16 @@ fn open_and_validate(
             name.to_string(),
         ),
         other => {
-            return Err(MagnotiaError::AudioCaptureFailed(format!(
+            return Err(Error::AudioCaptureFailed(format!(
                 "unsupported sample format {other:?}"
             )))
         }
     }
-    .map_err(|e| MagnotiaError::AudioCaptureFailed(format!("build_input_stream: {e}")))?;
+    .map_err(|e| Error::AudioCaptureFailed(format!("build_input_stream: {e}")))?;
 
     stream
         .play()
-        .map_err(|e| MagnotiaError::AudioCaptureFailed(format!("stream.play: {e}")))?;
+        .map_err(|e| Error::AudioCaptureFailed(format!("stream.play: {e}")))?;
 
     // Validation window: collect chunks for DEVICE_VALIDATION_MS, compute RMS.
     let deadline =
@@ -460,7 +460,7 @@ fn open_and_validate(
     }
 
     if total_samples == 0 {
-        return Err(MagnotiaError::AudioCaptureFailed(
+        return Err(Error::AudioCaptureFailed(
             "device delivered zero samples in validation window".into(),
         ));
     }
@@ -475,7 +475,7 @@ fn open_and_validate(
     );
 
     if require_audio && rms < SILENCE_RMS_FLOOR {
-        return Err(MagnotiaError::AudioCaptureFailed(format!(
+        return Err(Error::AudioCaptureFailed(format!(
             "device produced silence (rms={rms:.6} below floor {SILENCE_RMS_FLOOR:.6})"
         )));
     }
@@ -485,7 +485,7 @@ fn open_and_validate(
     // long stream of f32 zeros from a borked device — that is worse than
     // failing fast.
     if rms < DEAD_SILENCE_FLOOR {
-        return Err(MagnotiaError::AudioCaptureFailed(format!(
+        return Err(Error::AudioCaptureFailed(format!(
             "device produced dead silence (rms={rms:.6e} below absolute floor {DEAD_SILENCE_FLOOR:.6e})"
         )));
     }