releaseparser: adopt fixed positional model, auto-detect catalogues, add GB doc-blocks

Parse releases with an explicit fixed positional model and document the
whole logic in British English doc-blocks.

Model:
- [0]=Artist, [1]=Title are fixed and never matched against dictionaries,
  so titles like "Split"/"Demo"/"De" are never eaten.
- [len-1]=Group is always read from the line, not from the query key.
- [len-2]=Year when it is a 4-digit 19xx|20xx token; otherwise the slot is
  resolved as a middle-zone token (e.g. FLAC still picked up as format).
- The middle zone is resolved via case-insensitive dictionaries in the order
  format -> source -> bit-depth -> resolution -> edition -> language ->
  catalogue number. Position within the zone is irrelevant.

Catalogue numbers:
- Any "(...)" token in the middle zone is a catalogue number regardless of
  content (digits, roman numerals, dots, underscores, mixed case). Removed
  the hasDigit requirement and character whitelist that rejected real
  catalogues like (DYN.3140-2) and (GOWP_DCCCLXXXIX).
- Splitting never breaks tokens inside parentheses.

Case handling: lookups are case-insensitive; stored values keep their
original case from the line.

Documentation: replaced Ukrainian comments in parser.go and analyzer.go with
British-English doc-blocks describing the model, tail resolution order,
catalogue rule and confidence scoring.

Tests:
- Add TestParseCatalogNumberWithDotAndRoman for (DYN.3140-2)/(GOWP_DCCCLXXXIX).
- Update case-insensitive, split-title, no-year and language expectations.
- go build, go vet and go test all pass.

cmd/srrdb/main.go

@@ -55,5 +55,25 @@ func main() {
 		log.Fatal(err)
 	}
 
+	// Ручна ревізія: всі невідомі токени — у файл для правки бази.
+	review, err := os.OpenFile("review_unknown_tokens.txt",
+		os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer review.Close()
+	for releaser, stats := range out {
+		for _, unk := range stats.UnknownTokens {
+			for _, rel := range unk.Releases {
+				fmt.Fprintf(review, "%s\t%s\t%s\n", releaser, unk.Token, rel)
+			}
+		}
+		for _, warn := range stats.WarningStats {
+			for _, rel := range warn.Releases {
+				fmt.Fprintf(review, "%s\tWARN\t%s\t%s\n", releaser, warn.Token, rel)
+			}
+		}
+	}
+
 	fmt.Println(string(data))
 }