Save source descriptions, add "Why it's #N", fix IGDB studio names

Descriptions
- Items keep the source's description (TMDB/TheTVDB overview, IGDB
  summary, Wikipedia intro) in a new items.description column
  (migration 3); editable in the item form
- Deezer/MusicBrainz track counts and album names are now display-only
  hints, not saved as descriptions

Why it's #N
- The owner's note is presented as "Why it's #N" in the editor and the
  public detail view, above an "About" section with the description

IGDB developers
- IGDB credits internal divisions ("Nintendo EAD", "Nintendo EPD
  Production Group No. 8"). A developer whose name shares its first word
  with its parent company is credited to the parent ("Nintendo");
  independently named studios keep their name (Retro Studios, Naughty
  Dog, Landfall Games)
- Fall back to the publisher when IGDB lists no developer

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

internal/providers/igdb.go

@@ -2,6 +2,7 @@ package providers
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -9,6 +10,7 @@ import (
 	"strings"
 	"sync"
 	"time"
+	"unicode"
 )
 
 // igdb searches the Internet Game Database, authenticating through Twitch.
@@ -59,7 +61,7 @@ func (g *igdb) token(ctx context.Context, fresh bool) (string, error) {
 func (g *igdb) Search(ctx context.Context, query string) ([]Result, error) {
 	q := strings.NewReplacer(`\`, ``, `"`, `\"`).Replace(query)
 	body := `search "` + q + `";
-fields name,first_release_date,cover.image_id,summary,url,involved_companies.developer,involved_companies.company.name,platforms.abbreviation,platforms.name;
+fields name,first_release_date,cover.image_id,summary,url,involved_companies.developer,involved_companies.publisher,involved_companies.company.name,involved_companies.company.parent.name,involved_companies.company.parent.parent.name,involved_companies.company.parent.parent.parent.name,platforms.abbreviation,platforms.name;
 limit 25;`
 	var games []struct {
 		ID               int64  `json:"id"`
@@ -70,13 +72,8 @@ limit 25;`
 		Cover            struct {
 			ImageID string `json:"image_id"`
 		} `json:"cover"`
-		InvolvedCompanies []struct {
-			Developer bool `json:"developer"`
-			Company   struct {
-				Name string `json:"name"`
-			} `json:"company"`
-		} `json:"involved_companies"`
-		Platforms []struct {
+		InvolvedCompanies []igdbInvolved `json:"involved_companies"`
+		Platforms         []struct {
 			Abbreviation string `json:"abbreviation"`
 			Name         string `json:"name"`
 		} `json:"platforms"`
@@ -104,12 +101,7 @@ limit 25;`
 	}
 	out := make([]Result, 0, len(games))
 	for _, gm := range games {
-		var devs, plats []string
-		for _, ic := range gm.InvolvedCompanies {
-			if ic.Developer && ic.Company.Name != "" {
-				devs = append(devs, ic.Company.Name)
-			}
-		}
+		var plats []string
 		for _, p := range gm.Platforms {
 			name := p.Abbreviation
 			if name == "" {
@@ -121,9 +113,9 @@ limit 25;`
 			Provider:    "igdb",
 			ProviderID:  strconv.FormatInt(gm.ID, 10),
 			Title:       gm.Name,
-			Subtitle:    strings.Join(devs, ", "),
+			Subtitle:    strings.Join(igdbStudios(gm.InvolvedCompanies), ", "),
 			ExternalURL: gm.URL,
-			Overview:    truncate(gm.Summary, 600),
+			Overview:    truncate(gm.Summary, maxDescription),
 			Extra:       map[string]string{},
 		}
 		if gm.FirstReleaseDate > 0 {
@@ -139,3 +131,92 @@ limit 25;`
 	}
 	return out, nil
 }
+
+type igdbInvolved struct {
+	Developer bool        `json:"developer"`
+	Publisher bool        `json:"publisher"`
+	Company   igdbCompany `json:"company"`
+}
+
+// igdbStudios names who made a game: its developers, or its publishers when
+// IGDB lists no developer, with internal divisions credited to their company.
+func igdbStudios(involved []igdbInvolved) []string {
+	var devs, pubs []string
+	for _, ic := range involved {
+		if ic.Company.Name == "" {
+			continue
+		}
+		if ic.Developer {
+			devs = appendUnique(devs, studioName(&ic.Company))
+		}
+		if ic.Publisher {
+			pubs = appendUnique(pubs, studioName(&ic.Company))
+		}
+	}
+	if len(devs) == 0 {
+		return pubs
+	}
+	return devs
+}
+
+// igdbCompany is a company with as much of its parent chain as was
+// requested. IGDB sends an unexpanded parent as a bare ID, which is ignored.
+type igdbCompany struct {
+	Name   string
+	Parent *igdbCompany
+}
+
+func (c *igdbCompany) UnmarshalJSON(b []byte) error {
+	if len(b) == 0 || b[0] != '{' {
+		return nil
+	}
+	var raw struct {
+		Name   string       `json:"name"`
+		Parent *igdbCompany `json:"parent"`
+	}
+	if err := json.Unmarshal(b, &raw); err != nil {
+		return err
+	}
+	c.Name, c.Parent = raw.Name, raw.Parent
+	if c.Parent != nil && c.Parent.Name == "" {
+		c.Parent = nil
+	}
+	return nil
+}
+
+// studioName credits an internal division to the company it belongs to.
+// IGDB lists the exact team, so Super Mario Sunshine's developer is
+// "Nintendo EAD" and DK Bananza's is "Nintendo EPD Production Group No. 8".
+// When a studio's name starts with the same word as its parent's, it's a
+// division of that company and we show the parent ("Nintendo"). Studios
+// with their own identity keep their name: Retro Studios (owned by
+// Nintendo) or Naughty Dog (owned by Sony).
+func studioName(c *igdbCompany) string {
+	for c.Parent != nil && sameFirstWord(c.Name, c.Parent.Name) {
+		c = c.Parent
+	}
+	return c.Name
+}
+
+func sameFirstWord(a, b string) bool {
+	first := func(s string) string {
+		f := strings.FieldsFunc(strings.ToLower(s), func(r rune) bool {
+			return !unicode.IsLetter(r) && !unicode.IsDigit(r)
+		})
+		if len(f) == 0 {
+			return ""
+		}
+		return f[0]
+	}
+	fa := first(a)
+	return fa != "" && fa == first(b)
+}
+
+func appendUnique(list []string, s string) []string {
+	for _, x := range list {
+		if x == s {
+			return list
+		}
+	}
+	return append(list, s)
+}