feat: read-only IPMI driver; report a missing Redfish license (0.2.0)

A Supermicro X10DRL-i refuses Redfish without a license (SUM, DCMS or
OOB), even the service root. IPMI answers without one.

- New entry point `ipmi` (napalm_redfish.ipmi.IpmiDriver) on
  ManagementControllerDriver, over pyghmi: facts and inventory from the
  FRU (serial number, system UUID), the BMC's LAN interface, sensors
  (temperatures, fans, power supplies), the power state, the event log
  and the BMC firmware. Read-only: no power control, no BMC reset.
  Tested against recordings of the X10 with serials, the UUID, MACs and
  IPs replaced.
- RedfishDriver.open() no longer fails on a license refusal: get_facts
  returns what is known without Redfish, get_device_warnings reports
  bmc_license_required with the licenses the BMC names, every other
  getter raises. netOrk then shows the reason instead of an offline BMC.
- IpmiDriver is not exported from the package: NAPALM's own
  get_network_driver("redfish") takes the first driver class of
  napalm_redfish.

CHANGELOG.md

@@ -7,6 +7,24 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.2.0] - 2026-10-13
+
+### Added
+- `ipmi` NAPALM driver (`IpmiDriver`) on `ManagementControllerDriver`, read-only, over IPMI
+  2.0 with `pyghmi`: facts and inventory from the FRU (manufacturer, product, serial number,
+  system UUID), the BMC's LAN interface, temperatures, fans and power supplies from the
+  sensor records, the power state, the system event log and the BMC firmware version. No
+  power control and no BMC reset. For BMCs that refuse or lack Redfish; IPMI over LAN leaks
+  password hashes (CVE-2013-4786), so it is the fallback, not the main path.
+- Recorded IPMI fixtures from a Supermicro X10DRL-i (BMC 3.91).
+
+### Changed
+- A BMC that refuses Redfish for want of a vendor license no longer fails `open()`.
+  `get_facts` returns what is known without Redfish, `get_device_warnings` reports
+  `bmc_license_required` with the licenses the BMC names, and every other getter raises
+  `ConnectionException`. A poll therefore reports the missing license instead of an
+  offline BMC.
+
 ## [0.1.2] - 2026-10-13
 
 ### Fixed