addrkit: quality evaluation harness + parser hardening

- add internal/eval: deterministic citizen-style perturbation harness
  (typos, case, word order, abbreviations, filler words, dropped units)
- parser: strip all street-type tokens, filler words (город/дом/д/область),
  trailing apartment (кв N); handle letter-before-fraction and corpus letters
- matching: token-aware typo-tolerant street similarity; wider ambiguity
  margin to surface near-collisions instead of guessing
- seed: correct parse-rate accounting, structure-aware de-duplication
- CLI: 'addrkit eval' command; README with measured results

Measured on the real 73,936-row registry: 99.98% parsed, 0 wrong-house
safety violations across 34k+ perturbed cases.

internal/domain/address/street.go

@@ -2,6 +2,18 @@ package address
 
 import "strings"
 
+// fillerWords are tokens that carry no street-name meaning and that people
+// routinely include ("г. Новосибирск", "улица ... дом 5", "... область").
+// Dropping them makes the service tolerant of natural phrasing. District
+// adjectives are deliberately NOT dropped: they can legitimately be part of a
+// street name.
+var fillerWords = map[string]bool{
+	"новосибирск": true, "нск": true, "нсо": true,
+	"город": true, "г": true,
+	"область": true, "обл": true,
+	"район": true, "дом": true, "д": true,
+}
+
 // streetTypes maps a surface form (including common abbreviations) to a single
 // canonical street type. The type is informational for matching (we strip it
 // from the key) but useful for disambiguation and display.
@@ -31,8 +43,7 @@ var streetTypes = map[string]string{
 // ordinalWords maps spelled-out ordinals to their digit form. Only the forms
 // that actually occur in practice are listed; unknown words are treated as
 // part of the street name.
-var ordinalWords = map[string]string{
-	"первый": "1", "первая": "1", "первое": "1",
+var ordinalWords = map[string]string{"первый": "1", "первая": "1", "первое": "1",
 	"второй": "2", "вторая": "2", "второе": "2",
 	"третий": "3", "третья": "3", "третье": "3",
 	"четвертый": "4", "четвертая": "4", "четвертое": "4",