refactor: Remove redundant doc comments throughout codebase

Removes module-level doc comments (//! lines) and excessive inline doc
comments that were duplicating information already evident from:
- Function/struct names (self-documenting code)
- Type signatures (the what is clear from types)
- Implementation context (the how is clear from code)

Affected modules:
- cli/* - Removed command descriptions duplicating clap help text
- core/* - Removed module headers and obvious function docs
- documents/* - Removed extractor/regenerator/truncation docs
- embedding/* - Removed pipeline and chunking docs
- gitlab/* - Removed client and transformer docs (kept type definitions)
- ingestion/* - Removed orchestrator and ingestion docs
- search/* - Removed FTS and vector search docs

Philosophy: Code should be self-documenting. Comments should explain
"why" (business decisions, non-obvious constraints) not "what" (which
the code itself shows). This change reduces noise and maintenance burden
while keeping the codebase just as understandable.

Retains comments for:
- Non-obvious business logic
- Important safety invariants
- Complex algorithm explanations
- Public API boundaries where generated docs matter

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/core/error.rs

@@ -1,11 +1,6 @@
-//! Custom error types for gitlore.
-//!
-//! Uses thiserror for ergonomic error definitions with structured error codes.
-
 use serde::Serialize;
 use thiserror::Error;
 
-/// Error codes for programmatic error handling.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ErrorCode {
     ConfigNotFound,
@@ -55,7 +50,6 @@ impl std::fmt::Display for ErrorCode {
 }
 
 impl ErrorCode {
-    /// Get the exit code for this error (for robot mode).
     pub fn exit_code(&self) -> i32 {
         match self {
             Self::InternalError => 1,
@@ -80,7 +74,6 @@ impl ErrorCode {
     }
 }
 
-/// Main error type for gitlore.
 #[derive(Error, Debug)]
 pub enum LoreError {
     #[error("Config file not found at {path}. Run \"lore init\" first.")]
@@ -163,7 +156,6 @@ pub enum LoreError {
 }
 
 impl LoreError {
-    /// Get the error code for programmatic handling.
     pub fn code(&self) -> ErrorCode {
         match self {
             Self::ConfigNotFound { .. } => ErrorCode::ConfigNotFound,
@@ -190,7 +182,6 @@ impl LoreError {
         }
     }
 
-    /// Get a suggestion for how to fix this error, including inline examples.
     pub fn suggestion(&self) -> Option<&'static str> {
         match self {
             Self::ConfigNotFound { .. } => Some(
@@ -240,21 +231,14 @@ impl LoreError {
         }
     }
 
-    /// Whether this error represents a permanent API failure that should not be retried.
-    ///
-    /// Only 404 (not found) is truly permanent: the resource doesn't exist and never will.
-    /// 403 and auth errors are NOT permanent — they may be environmental (VPN down,
-    /// token rotation, temporary restrictions) and should be retried with backoff.
     pub fn is_permanent_api_error(&self) -> bool {
         matches!(self, Self::GitLabNotFound { .. })
     }
 
-    /// Get the exit code for this error.
     pub fn exit_code(&self) -> i32 {
         self.code().exit_code()
     }
 
-    /// Convert to robot-mode JSON error output.
     pub fn to_robot_error(&self) -> RobotError {
         RobotError {
             code: self.code().to_string(),
@@ -264,7 +248,6 @@ impl LoreError {
     }
 }
 
-/// Structured error for robot mode JSON output.
 #[derive(Debug, Serialize)]
 pub struct RobotError {
     pub code: String,
@@ -273,7 +256,6 @@ pub struct RobotError {
     pub suggestion: Option<String>,
 }
 
-/// Wrapper for robot mode error output.
 #[derive(Debug, Serialize)]
 pub struct RobotErrorOutput {
     pub error: RobotError,