feat: implement file upload handler and related functionality

- Added file upload handler to process both multipart and raw file uploads.
- Implemented parsing logic for upload requests, including handling file metadata.
- Introduced SaveFileDecodedInput structure for handling decoded file uploads.
- Created unit tests for file upload parsing and validation.

feat: add metadata retry configuration and functionality

- Introduced MetadataRetryConfig to the application configuration.
- Implemented MetadataRetryer to handle retrying metadata extraction for thoughts.
- Added new tool for retrying failed metadata extractions.
- Updated thought metadata structure to include status and timestamps for metadata processing.

fix: enhance metadata normalization and error handling

- Updated metadata normalization functions to track status and errors.
- Improved handling of metadata extraction failures during thought updates and captures.
- Ensured that metadata status is correctly set during various operations.

refactor: streamline file saving logic in FilesTool

- Refactored Save method in FilesTool to utilize new SaveDecoded method.
- Simplified project and thought ID resolution logic during file saving.

internal/types/thought.go

@@ -7,13 +7,17 @@ import (
 )
 
 type ThoughtMetadata struct {
-	People         []string            `json:"people"`
-	ActionItems    []string            `json:"action_items"`
-	DatesMentioned []string            `json:"dates_mentioned"`
-	Topics         []string            `json:"topics"`
-	Type           string              `json:"type"`
-	Source         string              `json:"source"`
-	Attachments    []ThoughtAttachment `json:"attachments,omitempty"`
+	People                  []string            `json:"people"`
+	ActionItems             []string            `json:"action_items"`
+	DatesMentioned          []string            `json:"dates_mentioned"`
+	Topics                  []string            `json:"topics"`
+	Type                    string              `json:"type"`
+	Source                  string              `json:"source"`
+	Attachments             []ThoughtAttachment `json:"attachments,omitempty"`
+	MetadataStatus          string              `json:"metadata_status,omitempty"`
+	MetadataUpdatedAt       string              `json:"metadata_updated_at,omitempty"`
+	MetadataLastAttemptedAt string              `json:"metadata_last_attempted_at,omitempty"`
+	MetadataError           string              `json:"metadata_error,omitempty"`
 }
 
 type ThoughtAttachment struct {