feat(editing): Live/Source editing modes (PSE v1)

Cargo.toml

@@ -32,7 +32,7 @@ eframe = { version = "0.33", default-features = false, features = [
 egui = { version = "0.33", features = ["accesskit"] }
 
 # MCP bridge for E2E testing (optional, local dev only - not on crates.io)
-# egui-mcp-bridge = { path = "/home/ahmet/dev/mcp/egui-mcp/crates/egui-mcp-bridge", optional = true }
+egui-mcp-bridge = { path = "/home/ahmet/dev/mcp/egui-mcp/crates/egui-mcp-bridge", optional = true }
 
 # Markdown rendering with syntax highlighting (fork with typography support)
 egui_commonmark_extended = { version = "0.28.2", features = [
@@ -73,7 +73,7 @@ percent-encoding = "2.3"
 
 [features]
 default = []
-# mcp = ["dep:egui-mcp-bridge"]
+mcp = ["dep:egui-mcp-bridge"]
 
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ['cfg(feature, values("mcp"))'] }

crates/egui_commonmark/egui_commonmark/src/lib.rs

@@ -94,7 +94,14 @@ pub use egui_commonmark_backend_extended::RenderHtmlFn;
 pub use egui_commonmark_backend_extended::RenderMathFn;
 pub use egui_commonmark_backend_extended::alerts::{Alert, AlertBundle};
 pub use egui_commonmark_backend_extended::misc::{
-    header_position_key, CommonMarkCache, STRONG_FONT_FAMILY,
+    header_position_key, CommonMarkCache, EditFeedback, EditRegionConfig, STRONG_FONT_FAMILY,
+};
+pub use egui_commonmark_backend_extended::misc::{BlockBoundary, top_level_block_spans};
+pub use egui_commonmark_backend_extended::misc::{
+    EditSessionConfig, SessionBlock, SessionBlockFeedback,
+};
+pub use egui_commonmark_backend_extended::styler::{
+    EditBlockKind, MarkdownEditStyle, markdown_block_job,
 };
 pub use egui_commonmark_backend_extended::typography::{Measurement, TypographyConfig};
 #[cfg(feature = "math")]
@@ -481,6 +488,32 @@ impl<'f> CommonMarkViewer<'f> {
         self
     }
 
+    /// Live-preview editing: replace the given top-level block byte range
+    /// with an inline TextEdit for this frame. The editor's working buffer
+    /// lives in egui temp state under `EditRegionConfig::id`; collect it via
+    /// [`CommonMarkCache::take_edit_feedback`] right after painting and splice
+    /// changed text back into your own buffer.
+    pub fn edit_region(mut self, region: Option<EditRegionConfig>) -> Self {
+        self.options.edit_region = region;
+        self
+    }
+
+    /// Persistent editing session: every text block in `blocks` paints as a
+    /// styled TextEdit bound to per-block temp buffers; other blocks render
+    /// normally. Collect per-block results via
+    /// [`CommonMarkCache::take_session_feedback`] right after painting.
+    pub fn edit_session(mut self, session: Option<EditSessionConfig>) -> Self {
+        self.options.edit_session = session;
+        self
+    }
+
+    /// Record block boundaries while painting so the caller can hit-test
+    /// clicks into byte ranges via [`CommonMarkCache::block_span_at_content_y`].
+    pub fn record_block_layout(mut self, on: bool) -> Self {
+        self.options.record_block_layout = on;
+        self
+    }
+
     /// Paint the complete document this frame so off-screen target positions
     /// can be measured. Keep this disabled for scrolling to a cached position.
     pub fn force_full_render(mut self, force: bool) -> Self {