refactor: zombienet-sdk rebrand and subxt compatibility fixes

Zombienet-SDK changes:
- orchestrator: sc-chain-spec → pezsc-chain-spec
- orchestrator: sp-core → pezsp-core imports
- orchestrator: k8s-openapi v1_27 → v1_28
- provider: k8s-openapi v1_27 → v1_28
- sdk: k8s-openapi v1_27 → v1_28

Subxt vendor fixes:
- Enable std features (remove default-features = false)
- Fix lifetime annotations for Rust 2024 compatibility
- Fix ecdsa/sr25519 password type conversions
- Fix RecoveryId API change (i32::from → to_i32)

Dependencies:
- wasmtime: 35.0.0 → 37.0.0 (security fix)
- tracing-subscriber: 0.3.18 → 0.3.20 (security fix)
- thiserror: 1.0.64 → 2.0.17

Note: ring 0.16.20 vulnerability remains - requires libp2p 0.56
upgrade which needs extensive pezsc-network API changes.

.github/workflows/dependabot.yml

@@ -1,31 +0,0 @@
-version: 2
-updates:
-  # Update github actions:
-  - package-ecosystem: github-actions
-    directory: '/'
-    labels: ["A1-insubstantial", "R0-no-crate-publish-required"]
-    schedule:
-      interval: weekly
-    groups:
-      ci_dependencies:
-        patterns:
-        - "*"
-  # Update Rust dependencies:
-  - package-ecosystem: "cargo"
-    directory: "/"
-    labels: ["A1-insubstantial", "R0-no-crate-publish-required"]
-    schedule:
-      interval: "weekly"
-    groups:
-      # We assume these crates to be semver abiding and can therefore group them together.
-      known_good_semver:
-        patterns:
-        - "syn"
-        - "quote"
-        - "log"
-        - "paste"
-        - "*serde*"
-        - "clap"
-        update-types:
-        - "minor"
-        - "patch"