docs: tambah doc comment, logging, dan inline comments di semua 255 file

Meliputi:
- File-level //! doc comment: tujuan file, alur kerja, komponen utama
- Function-level /// doc comment: apa, parameter, return, flow, edge cases
- Struct/enum/trait /// doc comment: peran, field docs
- Tracing logging (tracing::info!/debug!/trace!/warn!/error!) di setiap fungsi
- Inline comments untuk variable dan branching logic penting
- Seluruh 8 crates di workspace: zesdex-backend, zesdex-cms, zesdex-entities,
  zesdex-iam, zesdex-infra, zesdex-ipc, zesdex-middleware, zesdex-utils
- Build: 0 errors, 242/242 tests passed

crates/zesdex-backend/src/view/sidebar.rs

@@ -8,11 +8,21 @@ use ratatui::style::{Modifier, Style};
 use ratatui::text::{Line, Span};
 use ratatui::widgets::{Block, Borders, Paragraph};
 use ratatui::Frame;
+use tracing;
 
 /// Render the persistent right-hand dashboard: Workflow, Tasks, and Usage
 /// widgets stacked in three roughly-equal vertical thirds.
+///
+/// Flow: check whether the workflow engine has active agents (which
+/// determines the vertical split ratios) → partition the sidebar area
+/// into three stacked chunks → delegate each chunk to its widget fn.
 pub fn draw_sidebar(frame: &mut Frame, area: Rect, state: &crate::app::state::rest::AppStateRest) {
     let has_workflow = !state.workflow_engine.agents.is_empty();
+    tracing::debug!(
+        area = %format!("{}x{}", area.width, area.height),
+        has_workflow,
+        "draw_sidebar"
+    );
 
     let constraints = if has_workflow {
         vec![
@@ -40,7 +50,11 @@ pub fn draw_sidebar(frame: &mut Frame, area: Rect, state: &crate::app::state::re
 
 /// Compact Tasks widget: `misc.todo_content` split into lines, truncated
 /// to whatever fits with a trailing "+N more" hint pointing at `/todo`.
+///
+/// Flow: measure available height → split todo_content into lines →
+/// trim to fit → render inside a bordered block.
 fn draw_tasks_widget(frame: &mut Frame, area: Rect, state: &crate::app::state::rest::AppStateRest) {
+    tracing::debug!(area = %format!("{}x{}", area.width, area.height), "draw_tasks_widget");
     let block = Block::default()
         .title(Span::styled(
             " Tasks ",
@@ -100,6 +114,7 @@ fn draw_tasks_widget(frame: &mut Frame, area: Rect, state: &crate::app::state::r
 /// line silently clips (no `.wrap()` on this `Paragraph`) once token
 /// counts reach 5-6 digits, which is routine for an agent session.
 fn draw_usage_widget(frame: &mut Frame, area: Rect, state: &crate::app::state::rest::AppStateRest) {
+    tracing::debug!(area = %format!("{}x{}", area.width, area.height), "draw_usage_widget");
     let block = Block::default()
         .title(Span::styled(
             " Usage ",
@@ -176,6 +191,13 @@ pub(crate) fn compute_usage_summary(
     session_start: i64,
     now_ms: i64,
 ) -> UsageSummary {
+    tracing::debug!(
+        tokens_in = usage.tokens_in,
+        tokens_out = usage.tokens_out,
+        review_tokens = usage.review_tokens,
+        api_calls = usage.api_calls,
+        "compute_usage_summary"
+    );
     let total_tokens = usage.tokens_in.saturating_add(usage.tokens_out);
     let self_learning_tokens = usage.review_tokens;
     let main_tokens = total_tokens.saturating_sub(self_learning_tokens);