feat(config): add RealClientMode infrastructure for multi-version support

Add client version mode support to enable version-specific behavior:

- Add Mode type with constants for all game versions (S1.0 through ZZ)
- Add ClientMode (string) and RealClientMode (Mode) to Config
- Add ClanMemberLimits to GameplayOptions for configurable clan sizes
- Add MaximumFP to GameplayOptions for festa points cap
- Parse ClientMode string to RealClientMode enum in LoadConfig
- Set sensible defaults (ZZ for mode, standard limits for clans)
- Update config.example.json with new fields

This enables cherry-picking version-specific fixes from main branch.

config.example.json

@@ -12,6 +12,7 @@
   "ScreenshotAPIURL": "",
   "DeleteOnSaveCorruption": false,
   "DevMode": true,
+  "ClientMode": "ZZ",
   "DevModeOptions": {
     "AutoCreateAccount": true,
     "CleanDB": false,
@@ -39,6 +40,7 @@
     "DisableBoostTime": false,
     "BoostTimeDuration": 120,
     "ClanMealDuration": 3600,
+    "ClanMemberLimits": [[0, 30], [3, 40], [7, 50], [10, 60]],
     "BonusQuestAllowance": 3,
     "DailyQuestAllowance": 1
   },

config/config.go

@@ -11,6 +11,68 @@ import (
 	"github.com/spf13/viper"
 )
 
+// Mode represents the client version/mode
+type Mode int
+
+// Client version constants
+const (
+	S1 Mode = iota + 1
+	S15
+	S2
+	S25
+	S3
+	S35
+	S4
+	S5
+	S55
+	S6
+	S7
+	S8
+	S85
+	S9
+	S10
+	F1
+	F2
+	F3
+	F4
+	F5
+	G1
+	G2
+	G3
+	G31
+	G32
+	GG
+	G5
+	G51
+	G52
+	G6
+	G61
+	G7
+	G8
+	G81
+	G9
+	G91
+	G10
+	G101
+	Z1
+	Z2
+	ZZ
+)
+
+var versionStrings = []string{
+	"S1.0", "S1.5", "S2.0", "S2.5", "S3.0", "S3.5", "S4.0", "S5.0", "S5.5", "S6.0",
+	"S7.0", "S8.0", "S8.5", "S9.0", "S10", "FW.1", "FW.2", "FW.3", "FW.4", "FW.5",
+	"G1", "G2", "G3", "G3.1", "G3.2", "GG", "G5", "G5.1", "G5.2", "G6", "G6.1",
+	"G7", "G8", "G8.1", "G9", "G9.1", "G10", "G10.1", "Z1", "Z2", "ZZ",
+}
+
+func (m Mode) String() string {
+	if m < 1 || int(m) > len(versionStrings) {
+		return "Unknown"
+	}
+	return versionStrings[m-1]
+}
+
 // Config holds the global server-wide config.
 type Config struct {
 	Host                   string `mapstructure:"Host"`
@@ -24,6 +86,8 @@ type Config struct {
 	ScreenshotAPIURL       string   // Destination for screenshots uploaded to BBS
 	DeleteOnSaveCorruption bool     // Attempts to save corrupted data will flag the save for deletion
 	DevMode                bool
+	ClientMode             string // Client version string (e.g., "ZZ", "G10", "S6.0")
+	RealClientMode         Mode   // Parsed client mode for version checks
 
 	DevModeOptions  DevModeOptions
 	GameplayOptions GameplayOptions
@@ -63,15 +127,17 @@ type SaveDumpOptions struct {
 
 // GameplayOptions has various gameplay modifiers
 type GameplayOptions struct {
-	FeaturedWeapons     int    // Number of Active Feature weapons to generate daily
-	MaximumNP           int    // Maximum number of NP held by a player
-	MaximumRP           uint16 // Maximum number of RP held by a player
-	DisableLoginBoost   bool   // Disables the Login Boost system
-	DisableBoostTime    bool   // Disables the daily NetCafe Boost Time
-	BoostTimeDuration   int    // The number of minutes NetCafe Boost Time lasts for
-	ClanMealDuration    int    // Seconds that a Clan Meal can be activated for after cooking
-	BonusQuestAllowance uint32 // Number of Bonus Point Quests to allow daily
-	DailyQuestAllowance uint32 // Number of Daily Quests to allow daily
+	FeaturedWeapons     int         // Number of Active Feature weapons to generate daily
+	MaximumNP           int         // Maximum number of NP held by a player
+	MaximumRP           uint16      // Maximum number of RP held by a player
+	MaximumFP           uint32      // Maximum number of Festa Points held by a player
+	DisableLoginBoost   bool        // Disables the Login Boost system
+	DisableBoostTime    bool        // Disables the daily NetCafe Boost Time
+	BoostTimeDuration   int         // The number of minutes NetCafe Boost Time lasts for
+	ClanMealDuration    int         // Seconds that a Clan Meal can be activated for after cooking
+	ClanMemberLimits    [][]uint8   // Array of maximum Clan Members -> [[Rank, Members], ...]
+	BonusQuestAllowance uint32      // Number of Bonus Point Quests to allow daily
+	DailyQuestAllowance uint32      // Number of Daily Quests to allow daily
 }
 
 // Logging holds the logging configuration.
@@ -232,6 +298,24 @@ func LoadConfig() (*Config, error) {
 		c.Host = getOutboundIP4().To4().String()
 	}
 
+	// Parse ClientMode string to RealClientMode
+	c.RealClientMode = ZZ // Default to ZZ
+	if c.ClientMode != "" {
+		clientModeUpper := strings.ToUpper(c.ClientMode)
+		for i, vs := range versionStrings {
+			if clientModeUpper == vs {
+				c.RealClientMode = Mode(i + 1)
+				c.ClientMode = vs // Normalize the string
+				break
+			}
+		}
+	}
+
+	// Set default ClanMemberLimits if not configured
+	if len(c.GameplayOptions.ClanMemberLimits) == 0 {
+		c.GameplayOptions.ClanMemberLimits = [][]uint8{{0, 30}, {3, 40}, {7, 50}, {10, 60}}
+	}
+
 	return c, nil
 }