[luthermonson]

Wires the Redis commands that ePHPm v0.13.0's new ephpm_kv_* functions can serve.

What changes

• Hashes: HSET/HMSET, HGET, HMGET, HGETALL (flat reply, which Predis folds into an assoc array), HDEL, HEXISTS, HLEN, HKEYS, HVALS, HINCRBY, HSETNX.
• Field TTLs: HEXPIRE gives a per-field reply (1 = set, -2 = no field, 2 = deleted when seconds is 0). HTTL, HPTTL and HPERSIST are also handled per field. HEXPIRE's NX/XX/GT/LT conditions raise CommandNotSupportedException and are never ignored, because they would need a non-atomic read-then-write. HPEXPIRE and the *AT variants stay unsupported.
• Strings/keys: MGET, MSET, GETDEL, PERSIST, APPEND, STRLEN.
  • GETEX supports EX, PERSIST, no option, and PX when it is a whole number of seconds. Sub-second PX, EXAT and PXAT stay unsupported.
  • SCAN supports MATCH and COUNT. The reply is [cursor-as-string, keys], so Predis' Keyspace iterator works. The TYPE filter is unsupported. The README notes that in a cluster SCAN only sees this node's keyspace.
  • SET … IFEQ maps to ephpm_kv_set_if_eq. KEEPTTL is accepted together with IFEQ only.
• TYPE returns hash through ephpm_kv_type when that function exists.

Compatibility

• Feature detection: every command checks for its function(s) with function_exists. On an older ePHPm the command raises CommandNotSupportedException as it does today, and TYPE falls back to the exists-based answer.
• Error message: the exception message now lists the commands the running ePHPm actually supports.
• One exception changes: on an older ePHPm, SET … IFEQ used to throw InvalidArgumentException ("unknown SET modifier"). It now throws CommandNotSupportedException('SET IFEQ'), the same exception the other unsupported SET modifiers already throw.
• Backends: a backend opts in to the new commands through the new ExtendedKvOpsInterface, so existing custom KvOpsInterface implementations still compile.
• Test fake: InMemoryKvOps implements the new commands. new InMemoryKvOps([]) behaves like a runtime from before v0.13.

Tests

• New KvConnectionExtendedTest runs every mapping through a real Predis client, so Predis does its own response parsing.
• It also covers the fallback for each command (data provider), and a check that every EXTENDED_COMMANDS entry has a fallback case.
• SapiKvOpsTest adds cases for supports() and for passing calls through to the stubs.
• Ran locally with PHP 8.5.4 + PHPUnit 11.5: 121 tests OK.