feat(bf-3fka4): scaffold pdftract-inspector-ui crate

- Add crates/pdftract-inspector-ui as workspace member
- Create Cargo.toml with rlib crate type
- Add build.rs with 80 KB bundle size limit check (flate2-based gzip)
- Create src/lib.rs with include_bytes! for HTML/CSS/JS assets
- Add minimal frontend stub (static/index.html, style.css, app.js)
- Bundle size: 0.87 KB gzipped (well under 80 KB limit)

Closes bf-3fka4

.needle-predispatch-sha

@@ -1 +1 @@
-0753d48fed8678faf93fafb75a308141282f52c6
+56f8e613dac3aecb6c6a1cb4b061ca054c170a7b

crates/pdftract-cli/src/main.rs

@@ -584,6 +584,7 @@ fn main() -> Result<()> {
             cache_size,
             no_cache,
             md_anchors,
+            md_no_page_breaks,
             auto,
             profile,
             output,
@@ -613,6 +614,7 @@ fn main() -> Result<()> {
                 &cache_size,
                 no_cache,
                 md_anchors,
+                md_no_page_breaks,
                 auto,
                 profile,
                 include_headers,
@@ -894,6 +896,7 @@ fn cmd_extract(
     cache_size: &str,
     no_cache: bool,
     md_anchors: bool,
+    md_no_page_breaks: bool,
     auto: bool,
     profile: Option<String>,
     include_headers: bool,
@@ -1162,6 +1165,12 @@ fn cmd_extract(
         eprintln!("Markdown anchors enabled");
     }
 
+    // Set markdown page breaks option
+    options.markdown_no_page_breaks = md_no_page_breaks;
+    if md_no_page_breaks {
+        eprintln!("Markdown page breaks disabled (--md-no-page-breaks)");
+    }
+
     // Set OCR language if specified
     if !ocr_language.is_empty() {
         options.ocr_language = ocr_language;

crates/pdftract-core/src/options.rs

@@ -330,6 +330,15 @@ pub struct ExtractionOptions {
     /// Default: false (anchors disabled)
     pub markdown_anchors: bool,
 
+    /// Suppress page-break horizontal rules between consecutive pages in Markdown output (Phase 6.5.5).
+    ///
+    /// When enabled, the horizontal rule separator (`\n\n---\n\n`) between pages is omitted,
+    /// and pages are separated by double newlines only. This is useful for LLM ingestion
+    /// where page breaks add noise and chunking systems prefer continuous text.
+    ///
+    /// Default: false (page breaks enabled with `---` separator)
+    pub markdown_no_page_breaks: bool,
+
     /// Maximum decompressed bytes allowed per document (bomb limit).
     ///
     /// This limit prevents zip-bomb attacks where a small compressed PDF expands
@@ -427,6 +436,7 @@ impl Default for ExtractionOptions {
             ocr_dpi_override: None,
             ocr_language: vec!["eng".to_string()],
             markdown_anchors: false,
+            markdown_no_page_breaks: false,
             max_decompress_bytes: crate::parser::stream::DEFAULT_MAX_DECOMPRESS_BYTES,
             output: OutputOptions::default(),
             pages: None,
@@ -466,6 +476,7 @@ impl ExtractionOptions {
             ocr_dpi_override: None,
             ocr_language: vec!["eng".to_string()],
             markdown_anchors: false,
+            markdown_no_page_breaks: false,
             output: OutputOptions::default(),
             pages: None,
             password: None,

crates/pdftract-core/src/parser/object/cache.rs

@@ -35,6 +35,7 @@
 use super::cycle::{is_resolving, ResolutionGuard, RESOLVING};
 use super::{ObjRef, PdfObject};
 use crate::diagnostics::{DiagCode, Diagnostic as Diag};
+use std::cell::Cell;
 use std::sync::Arc;
 use std::sync::Mutex;
 use std::num::NonZeroUsize;
@@ -46,15 +47,24 @@ use lru::LruCache;
 /// adversarial input that could cause stack overflow through deep chains.
 const MAX_RESOLUTION_DEPTH: u16 = 256;
 
+/// Per-thread resolution depth counter.
+///
+/// Each thread gets its own independent depth counter, allowing concurrent
+/// page processing in rayon without lock contention.
+thread_local! {
+    /// Per-thread resolution depth counter for object reference chains.
+    static RESOLUTION_DEPTH: Cell<u16> = Cell::new(0);
+}
+
 /// RAII guard that manages both thread-local cycle detection and depth tracking.
 ///
 /// This guard:
 /// - Holds the cycle detection guard (manages thread-local set)
-/// - Holds a reference to the depth counter for cleanup on drop
+/// - Increments depth on creation, decrements on drop
 ///
 /// When dropped, the guard:
 /// - Removes the object reference from the thread-local cycle detection set
-/// - Decrements the depth counter
+/// - Decrements the thread-local depth counter
 ///
 /// This ensures proper cleanup even if:
 /// - The resolution function returns early
@@ -62,8 +72,6 @@ const MAX_RESOLUTION_DEPTH: u16 = 256;
 pub struct CacheResolutionGuard {
     /// The underlying cycle detection guard (manages thread-local set)
     _guard: ResolutionGuard,
-    /// Shared depth counter for cleanup on drop
-    depth: Arc<Mutex<u16>>,
 }
 
 impl std::fmt::Debug for CacheResolutionGuard {