Add XML-defined machines, generated screens and recipe bundles - #97

1. merge() matches inherited children by name+id, so a child machine that uses a different id for a single-valued element ends up with two siblings and fails to load.
2. One bad machine recipe or one failing generator throws IllegalArgumentException inside the reload listener's apply(), which aborts the whole data reload instead of skipping that recipe the way vanilla does.
3. key() gives every child without an id or name the same 'name:' key, and merge() puts children into a LinkedHashMap by key, so same-type siblings without ids collapse to the last one.
4. Adding <xs:anyAttribute processContents="skip"/> to templateContent turns off unknown-attribute checks on every <fill> and <placeholder>, including hand-written screens that never use generators.
5. The check that resource-group highlights point to existing screen elements was removed for all hosts, not only for XML machines (which compute their highlights from the screen and could never miss).
6. Every block-entity construction re-runs the Screens lookup, scans all screen elements once per group, and repeats ScreenInventoryValidation, although all of it depends only on the definition.
7. The reserved storage-ID list is a hand-copied duplicate of MachineInventoryLifecycle.RESERVED_KEYS (with 'energy' added) instead of reusing that set.
8. Processor-button icons and value labels are hard-coded space-separated lists that must match the order and count of ProcessorButtonState values; the stop icon is repeated three times to pad for STALLED, BLOCKED and HELD.
9. The same lambda that throws 'No generator context' is copied three times (ScreenLoader lines 42 and 104, ScreenTemplates line 24), and the BiFunction type is spelled out with full package names at each signature.
10. Float.parseFloat(hardness) and the ResourceLocation.parse calls (mineable, textures, extends, recipe-type) throw raw exceptions with no file and line, unlike the number()/color() helpers in the same file.

• if someone from a comma is the decimal separator nation writes a file using their national standard, it will break things with Float.parseFloat at a minimum.

2. Rejecting the candidate reload is intentional. Authored recipes and generators are validated as a complete set; a failure leaves the previously active recipes intact instead of publishing a partial set. This is covered by the failed-reload regression test.

3. Missing highlight targets are intentionally optional for every host. Throwing during menu construction could disconnect a player over a cosmetic screen mismatch. The drawer already skips missing targets, and XML machines derive theirs from the screen.

fixed all the rest

* should be 5 not 3 but github renders it wrong :)