feat: replace Lua config with Parmlib parser (DD:HTTPPRM)

Replace the Lua-based httpconf.c (1286 lines) with a line-based
KEY=VALUE Parmlib parser httpprm.c (540 lines) that reads from
DD:HTTPPRM.  Follows the same pattern as FTPD and UFSD.

- New src/httpprm.c: reads DD:HTTPPRM, KEY=VALUE format, comments
  with # or *, missing DD starts with defaults (warning)
- Delete src/httpconf.c: Lua config engine removed
- CGI registration via CGI=PROGRAM /path/* lines (no defaults)
- No MQTT or embedded FTPD initialization (confirmed removals)
- Socket bind with retry logic preserved from httpconf.c
- All settings carried over: PORT, MINTASK, MAXTASK, CLIENT_TIMEOUT,
  LOGIN, TZOFFSET, DEBUG, UFS, DOCROOT, CODEPAGE, BIND_TRIES,
  BIND_SLEEP, LISTEN_QUEUE, CGI, CGILUA_*, CLIENT_STATS_*, etc.

HTTPD struct changes:
- lua_State *config → void *unused_60 (preserve offsets)
- New fields: ufs_enabled, dbg_enabled, bind_tries, bind_sleep,
  listen_queue, codepage[16]

New samplib/ directory:
- samplib/httpd: STC JCL procedure (matching FTPD/UFSD pattern)
- samplib/httpprm0: sample Parmlib member with all settings

Fixes #40

Author: mgrossmann

include/httpd.h

@@ -126,7 +126,7 @@ struct httpd {
     UFSSYS      *ufssys;            /* 54 Unix like file system     */
     LUAX		*luax;				/* 58 Lua function vector		*/
     const char  *version;			/* 5C HTTPD Version				*/
-    lua_State   *config;			/* 60 Lua configuration state	*/
+    void        *unused_60;         /* 60 (was: lua_State *config)  */
     UCHAR		cfg_maxtask;		/* 64 config max task			*/
     UCHAR		cfg_mintask;		/* 65 config min task			*/
     UCHAR		cfg_client_timeout;	/* 66 client timeout seconds	*/
@@ -135,7 +135,10 @@ struct httpd {
     UCHAR		cfg_st_hour_max;	/* 69 statistics hour_records	*/
     UCHAR		cfg_st_min_max;		/* 6A statistics min records	*/
     UCHAR       cfg_cgictx;         /* 6B # CGI context pointers    */
-    UCHAR		cfg_st_unused[4];	/* 6C unused / available		*/
+    UCHAR       ufs_enabled;        /* 6C UFS filesystem enabled    */
+    UCHAR       dbg_enabled;        /* 6D debug output enabled      */
+    UCHAR       bind_tries;         /* 6E socket bind retry count   */
+    UCHAR       bind_sleep;         /* 6F socket bind retry delay   */
 	HTTPSTAT	**st_month;			/* 70 statistics month array	*/
     HTTPSTAT	**st_day;			/* 74 statistics day array 		*/
     HTTPSTAT	**st_hour;			/* 78 statistics hour array		*/
@@ -152,7 +155,10 @@ struct httpd {
 #define HTTPD_CGICTX_MIN    0       /* ... minimum number of cgictx */
 #define HTTPD_CGICTX_MAX    255     /* ... maximum number of cgictx */
     char        docroot[128];       /* A0 UFS document root prefix  */
-};                                  /* 120                          */
+    UCHAR       listen_queue;       /* 120 listen backlog           */
+    UCHAR       unused_121[3];      /* 121 alignment padding        */
+    char        codepage[16];       /* 124 codepage name            */
+};                                  /* 134                          */
 
 /* Telemetry */
 struct httpt {

project.toml

@@ -48,7 +48,7 @@ blksize = 15040
 space = ["TRK", 150, 50, 30]
 
 [dependencies]
-"mvslovers/crent370" = ">=1.0.7"
+"mvslovers/crent370" = ">=1.0.8"
 "mvslovers/ufsd" = "=1.0.0-dev"
 "mvslovers/lua370" = ">=1.0.2"
 "mvslovers/mqtt370" = ">=1.0.3"
@@ -60,7 +60,7 @@ space = ["TRK", 150, 50, 30]
 name = "HTTPD"
 entry = "@@CRT0"
 options = ["SIZE=(4000K,40K)", "LIST", "MAP", "XREF", "RENT"]
-include = ["@@CRT1", "HTTPSTRT", "HTTPD"]
+include = ["@@CRT1", "HTTPSTRT", "HTTPD", "HTTPPRM"]
 setcode = "AC(1)"
 
 [link.module.dep_includes]

samplib/httpd

@@ -0,0 +1,30 @@
+//HTTPD    PROC M=HTTPPRM0,
+//            D='SYS2.PARMLIB'
+//*
+//* HTTPD - HTTP Server STC Procedure
+//*
+//* Installation:
+//*   Copy to SYS2.PROCLIB(HTTPD)
+//*   Copy config member to SYS2.PARMLIB(HTTPPRM0)
+//*
+//* Starting:    /S HTTPD
+//*              /S HTTPD,M=HTTPPRM1     (alternate config member)
+//*              /S HTTPD,D='MY.PARMLIB'  (alternate parmlib dataset)
+//* Commands:    /F HTTPD,DISPLAY CONFIG
+//*              /F HTTPD,DISPLAY STATS
+//*              /F HTTPD,HELP
+//*              /F HTTPD,SHUTDOWN
+//* Stopping:    /P HTTPD
+//*
+//HTTPD    EXEC PGM=HTTPD,REGION=8M,TIME=1440
+//STEPLIB  DD  DISP=SHR,DSN=HTTPD.LINKLIB
+//SYSUDUMP DD  SYSOUT=*
+//HTTPDERR DD  SYSOUT=*
+//HTTPDOUT DD  SYSOUT=*
+//HTTPDIN  DD  DUMMY
+//SNAP     DD  SYSOUT=*
+//HTTPDBG  DD  SYSOUT=*
+//HTTPSTAT DD  SYSOUT=*
+//HTTPPRM  DD  DSN=&D(&M),DISP=SHR,FREE=CLOSE
+//HASPCKPT DD  DISP=SHR,DSN=SYS1.HASPCKPT,UNIT=3350,VOL=SER=MVS000
+//HASPACE1 DD  DISP=SHR,DSN=SYS1.HASPACE,UNIT=3350,VOL=SER=SPOOL1

samplib/httpprm0

@@ -0,0 +1,63 @@
+# HTTPD 4.0.0 Configuration
+#
+# Copy to SYS2.PARMLIB(HTTPPRM0)
+# Referenced by HTTPPRM DD in the STC JCL procedure.
+#
+# Format: KEY=VALUE (case-insensitive keys)
+# Lines starting with # or * are comments.
+#
+# --- Network ---
+PORT=8080
+BIND_TRIES=10
+BIND_SLEEP=10
+LISTEN_QUEUE=5
+#
+# --- Worker threads ---
+MINTASK=3
+MAXTASK=9
+CLIENT_TIMEOUT=10
+#
+# --- Security ---
+LOGIN=NONE
+#
+# --- Timezone ---
+# TZOFFSET=+01:00
+#
+# --- Codepage ---
+# CODEPAGE=CP037
+#
+# --- UFS Filesystem ---
+UFS=1
+DOCROOT=/www
+#
+# --- Debug ---
+DEBUG=0
+#
+# --- CGI Modules ---
+# Format: CGI=PROGRAM /url/path
+# No CGIs are registered by default.
+# Uncomment the lines below to enable them.
+#
+# CGI=MVSMF /zosmf/*
+# CGI=HTTPDSRV /.dsrv
+# CGI=HTTPDSL /dsl/*
+# CGI=HTTPJES2 /jes/*
+# CGI=HTTPLUA /lua/*
+# CGI=HTTPREXX /rexx/*
+# CGI=HTTPDM /.dm
+# CGI=HTTPDMTT /.dmtt
+# CGI=HELLO /hello
+#
+# --- Lua CGI Settings ---
+# CGILUA_DATASET=HTTPD.CGILUA
+# CGILUA_PATH=
+# CGILUA_CPATH=
+#
+# --- Statistics ---
+# CLIENT_STATS=1
+# CLIENT_STATS_MONTH_MAX=24
+# CLIENT_STATS_DAY_MAX=60
+# CLIENT_STATS_HOUR_MAX=48
+# CLIENT_STATS_MINUTE_MAX=120
+# CLIENT_STATS_DATASET=
+#