PKG-06: bump 0.6.0 -> 0.7.0, because the schema changed and nobody bumped

Six merges landed since 0.6.0 was deployed and the version never moved.
Disk and box both read 0.6.0, so `ha apps update` would have been a
NO-OP: Supervisor keys the built image by `version:`, and the update path
installs `version_latest`, which cannot differ from `version` without a
bump. Found while pre-checking the deploy, not after it silently did
nothing.

⚠️ MINOR RATHER THAN PATCH, BECAUSE THE SCHEMA CHANGED. SAFETY-32 added
`bms_soc_floor: int(0,50)` as a REQUIRED per-entry key on the `inverters`
roster - no trailing `?` - so a config declaring a roster and omitting it
on any entry is refused at startup. Verified against the deployed
2d025ee: the per-entry schema went from 6 keys to 7. Top-level options
and schema are unchanged at 63 each.

An install running `inverters: []` is unaffected, which is every
single-inverter install including the reference one: the flat
`bms_soc_floor` still describes the one pack. But CFG-04 recorded the
rule this follows - "a schema change without a bump is a schema nobody
reads" - and this is exactly that shape.

The CHANGELOG gains a 0.7.0 section listing the six merges by SHA. It
also records, rather than papers over, that 0.6.0 was never sectioned:
its content sits below the new heading because the earlier bump shipped
without cutting a section. Splitting it retroactively would mean guessing
a boundary; the deployed 0.6.0 is 2d025ee and the table says what is new
since it.

Full suite: 21 passed, 0 failed.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU

goodwe_controller/config.yaml

@@ -1,5 +1,5 @@
 name: GoodWe RS485 Controller
-version: "0.6.0"
+version: "0.7.0"
 slug: goodwe_controller
 description: >-
   Drives a GoodWe ES/BP battery inverter over RS485 by emulating its smart