[PHP] Share file-index path inspection

[adamziel]

File indexing and files-pull journal updates now derive path type, size, and ctime from one stat-record decoder.

Both paths were decoding the same Unix mode bits. There is no reason to maintain two answers for whether a path is a file, directory, link, or unsupported type. read_file_index_entry_from_stat() now owns that translation and the size normalization used by file indexes.

FileIndexProcessor still owns symlink targets and physical directory emptiness. PullIndexJournal still writes only the fields carried by its WAL. This changes no index format or pull behavior.

Tested with FileIndexProcessorTest, PullIndexWalTest, and FreshLocalIndexProcessorTest, plus the PHP 7.2 server and PHP 7.4 client compatibility scans.

[github-actions]

Pull pipeline performance — large-directory

Site: large-directory · 2,000+ plus targeted file-transfer scenarios files · 10,000 posts · 25,000 postmeta · PHP 8.5.9

Stage	PR	trunk	Δ	Status	Details
playground-sqlite-db-pull	7.06 s	7.07 s	⚪ -5 ms (-0.1%)	✓	condition=db-pull in PHP.wasm runtime=php.wasm 8.3 wp_mysql_parser=enabled mode=lexer native_lexer=verified native_token_stream=WP_MySQL_Native_Token_Stream native_token_count=18 native_parser=selected trunk: condition=db-pull in PHP.wasm runtime=php.wasm 8.3 wp_mysql_parser=enabled mode=lexer native_lexer=verified native_token_stream=WP_MySQL_Native_Token_Stream native_token_count=18 native_parser=selected
playground-sqlite-db-apply	2.72 s	2.72 s	⚪ +2 ms (+0.1%)	✓	condition=db-apply to SQLite in PHP.wasm runtime=php.wasm 8.3 wp_mysql_parser=enabled mode=parser native_lexer=verified native_token_stream=WP_MySQL_Native_Token_Stream native_token_count=18 native_parser=verified native_ast=WP_MySQL_Native_Parser_Node sqlite_driver_parser=verified trunk: condition=db-apply to SQLite in PHP.wasm runtime=php.wasm 8.3 wp_mysql_parser=enabled mode=parser native_lexer=verified native_token_stream=WP_MySQL_Native_Token_Stream native_token_count=18 native_parser=verified native_ast=WP_MySQL_Native_Parser_Node sqlite_driver_parser=verified
Total	9.78 s	9.79 s	⚪ -3 ms (-0.0%)

_{Numbers carry runner noise; treat single-run deltas as directional, not authoritative.}

_{📈 Trunk performance history — commit-by-commit timeline.}