P5a plan: PDF documents — seven Ornith tasks with acceptance tests first

docs/plans/p5a: 01 kind+fetch limits, 02 pdftext child + runner, 03 dcache PDF tables,
04 pdfpool, 05 pdfdoc render (map/pages/grep), 06 api, 07 digest citations, metrics, CLI,
skill, unit, README. Given tests compile against a panic-only skeleton and fail there for the
intended reasons; PDFs for tests are built by internal/pdftest (given), plus two qpdf-encrypted
fixtures.

Owner changes for the run: vendor go-pdfkit/extract v0.3.0 + reader v0.6.0 (pinned via
tools.go until task 02); AGENTS.md, tools/run-plan.sh (enforces a Co-Authored-By trailer for
the model), docs/implementer-log.md, `make gate`; gofmt (whitespace) on clean.go and guard;
TestUnsupportedType uses a zip now that PDFs are supported; requestDeadline 90→210 s and
writeTimeout 120→240 s for the PDF path's worst case.

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

vendor/github.com/go-pdfkit/pdffont/extended.go

@@ -0,0 +1,71 @@
+package pdffont
+
+// The glyph names above cover the Latin every English document is set in and
+// stop there. A document in Czech, Polish, Slovak, Hungarian, Turkish,
+// Romanian, Latvian, Lithuanian or Maltese is set in the block that follows,
+// and every one of its accented letters was being read as nothing at all —
+// which is worse than it sounds, because a dropped character leaves no mark:
+// "Příliš" comes back "Píliš" and looks like a word.
+//
+// Counted across the 118 833-file corpus: of 52.4 million glyph names, 483 382
+// could not be turned into text, and the largest nameable share of those was
+// this block — rcaron 650, zdotaccent 617, Ccaron 611, nacute 602, aogonek
+// 602, scedilla 597, gbreve 597, and so on for a hundred more.
+//
+// These are the names the Adobe Glyph List gives, and the characters are not
+// in doubt: unlike the subsetted fonts that call their glyphs g0 or dress a
+// glyph number up as uni00000048, a name like "rcaron" says exactly one thing.
+var latinExtendedRunes = map[string]rune{
+	"Amacron": 'Ā', "amacron": 'ā', "Abreve": 'Ă', "abreve": 'ă',
+	"Aogonek": 'Ą', "aogonek": 'ą', "Cacute": 'Ć', "cacute": 'ć',
+	"Ccircumflex": 'Ĉ', "ccircumflex": 'ĉ', "Cdotaccent": 'Ċ', "cdotaccent": 'ċ',
+	"Ccaron": 'Č', "ccaron": 'č', "Dcaron": 'Ď', "dcaron": 'ď',
+	"Dcroat": 'Đ', "dcroat": 'đ', "Dslash": 'Đ', "dmacron": 'đ',
+	"Emacron": 'Ē', "emacron": 'ē', "Ebreve": 'Ĕ', "ebreve": 'ĕ',
+	"Edotaccent": 'Ė', "edotaccent": 'ė', "Eogonek": 'Ę', "eogonek": 'ę',
+	"Ecaron": 'Ě', "ecaron": 'ě', "Gcircumflex": 'Ĝ', "gcircumflex": 'ĝ',
+	"Gbreve": 'Ğ', "gbreve": 'ğ', "Gdotaccent": 'Ġ', "gdotaccent": 'ġ',
+	"Gcommaaccent": 'Ģ', "gcommaaccent": 'ģ',
+	"Hcircumflex": 'Ĥ', "hcircumflex": 'ĥ', "Hbar": 'Ħ', "hbar": 'ħ',
+	"Itilde": 'Ĩ', "itilde": 'ĩ', "Imacron": 'Ī', "imacron": 'ī',
+	"Ibreve": 'Ĭ', "ibreve": 'ĭ', "Iogonek": 'Į', "iogonek": 'į',
+	"Idotaccent": 'İ', "dotlessi": 'ı', "IJ": 'IJ', "ij": 'ij',
+	"Jcircumflex": 'Ĵ', "jcircumflex": 'ĵ',
+	"Kcommaaccent": 'Ķ', "kcommaaccent": 'ķ', "kgreenlandic": 'ĸ',
+	"Lacute": 'Ĺ', "lacute": 'ĺ', "Lcommaaccent": 'Ļ', "lcommaaccent": 'ļ',
+	"Lcaron": 'Ľ', "lcaron": 'ľ', "Ldot": 'Ŀ', "ldot": 'ŀ',
+	"Nacute": 'Ń', "nacute": 'ń', "Ncommaaccent": 'Ņ', "ncommaaccent": 'ņ',
+	"Ncaron": 'Ň', "ncaron": 'ň', "napostrophe": 'ʼn', "Eng": 'Ŋ', "eng": 'ŋ',
+	"Omacron": 'Ō', "omacron": 'ō', "Obreve": 'Ŏ', "obreve": 'ŏ',
+	"Ohungarumlaut": 'Ő', "ohungarumlaut": 'ő',
+	"Racute": 'Ŕ', "racute": 'ŕ', "Rcommaaccent": 'Ŗ', "rcommaaccent": 'ŗ',
+	"Rcaron": 'Ř', "rcaron": 'ř', "Sacute": 'Ś', "sacute": 'ś',
+	"Scircumflex": 'Ŝ', "scircumflex": 'ŝ', "Scedilla": 'Ş', "scedilla": 'ş',
+	"Tcommaaccent": 'Ţ', "tcommaaccent": 'ţ', "Tcaron": 'Ť', "tcaron": 'ť',
+	"Tbar": 'Ŧ', "tbar": 'ŧ', "Utilde": 'Ũ', "utilde": 'ũ',
+	"Umacron": 'Ū', "umacron": 'ū', "Ubreve": 'Ŭ', "ubreve": 'ŭ',
+	"Uring": 'Ů', "uring": 'ů', "Uhungarumlaut": 'Ű', "uhungarumlaut": 'ű',
+	"Uogonek": 'Ų', "uogonek": 'ų', "Wcircumflex": 'Ŵ', "wcircumflex": 'ŵ',
+	"Ycircumflex": 'Ŷ', "ycircumflex": 'ŷ',
+	"Zacute": 'Ź', "zacute": 'ź', "Zdotaccent": 'Ż', "zdotaccent": 'ż',
+	"longs": 'ſ',
+
+	// A handful outside that block that the same documents use: the Romanian
+	// letters written with a comma below rather than a cedilla, the Turkish
+	// and Azeri schwa, and the two the Adobe list names for Welsh and Maltese.
+	"Scommaaccent": 'Ș', "scommaaccent": 'ș',
+	"Afii10017": 'А', "afii10017": 'А',
+	"Wgrave": 'Ẁ', "wgrave": 'ẁ', "Wacute": 'Ẃ', "wacute": 'ẃ',
+	"Wdieresis": 'Ẅ', "wdieresis": 'ẅ',
+	"Ygrave": 'Ỳ', "ygrave": 'ỳ',
+	"Hcaron": 'Ȟ', "hcaron": 'ȟ',
+	// The rest of what the corpus asks for and nothing could answer, each of
+	// them a name the Adobe list gives and none of them in doubt: the cedilla
+	// spellings of the Romanian letters, the capital sharp s, the script ell
+	// mathematicians write lengths with, and the angle brackets.
+	"Tcedilla": 'Ţ', "tcedilla": 'ţ', "Germandbls": 'ẞ',
+	"lscript": 'ℓ', "openbullet": '◦',
+	"angbracketleft": '〈', "angbracketright": '〉',
+	"Scommabelow": 'Ș', "scommabelow": 'ș',
+	"Tcommabelow": 'Ț', "tcommabelow": 'ț',
+}