Fields: table cells keep stored values, UPDATEFIELD reaches blocks and tables, measured shading box

Table cell fields show their stored value; only formula cells evaluate
live. UPDATEFIELD on a block reference also updates the fields of its
block definition, and on a table the fields of its cells; a changed
table cell text redraws the table. The FIELDDISPLAY box is placed from
the text layout (MTEXT layout cells, TEXT / attribute pen advances) and
spans 0.345 text heights below the baseline to 1.19 above it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Cargo.toml

@@ -95,7 +95,7 @@ iced_core = { git = "https://github.com/iced-rs/iced.git", rev = "23604ff22ab0aa
 iced_widget = { git = "https://github.com/iced-rs/iced.git", rev = "23604ff22ab0aad9e00b9327cb7b8546ed84db39" }
 
 [patch."https://github.com/HakanSeven12/opencadcodec.git"]
-opencadcodec = { git = "https://github.com/ramox81/cadcodec.git", rev = "4892548" }
+opencadcodec = { git = "https://github.com/ramox81/cadcodec.git", rev = "07191be" }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 getrandom = "0.3"