Module text_replace 

Text replacement in PDF content streams (legacy convenience API).

Since Phase 1C these functions are thin wrappers over the crate::text_edit engine (see docs/TEXT_REPLACE_ENGINE_DESIGN.md §9). They keep the historical count-only contract: per-occurrence failures are not errors, they simply do not count. Callers that need per-edit diagnostics, single-occurrence selection, signature protection or stream preservation guarantees should use crate::text_edit directly.

Behaviour changes relative to the pre-1C implementation (deliberate, each covered by a flipped characterization test):

• multiple /Contents streams are preserved instead of collapsed;
• text covered by /ActualText is left untouched instead of desynced;
• cross-run matches whose replacement needs a fallback font now succeed;
• TJ kerning outside the edited region is preserved;
• encrypted documents whose permissions forbid modification are refused.

Functions

replace_text

Replace all occurrences of search with replacement in a page’s content.

replace_text_all_pages

Replace text across all pages in a document.