Add proposals index and numbering process

This introduces a proposal index (README.md) for the proposals directory
to solve the problem of colliding proposal numbers.

Currently, multiple open PRs have chosen proposal numbers that conflict
with already-merged proposals. This creates confusion and makes it
difficult to maintain stable identifiers for proposals - which is
essential for productive discussion on the mailing list.

The new process:
1. Authors create proposals with temporary filenames (nnn-*)
2. A separate PR to this README allocates the next sequential number
3. Authors rename their proposal once the number is allocated
4. The index is updated again when proposals are accepted

This ensures:
- Proposal numbers are allocated chronologically
- No number collisions occur
- Each proposal gets a stable identifier before mailing list discussion
- Clear visibility of open vs. accepted proposals

Current collisions resolved by this index:
- PR kroxylicious#70, kroxylicious#82, kroxylicious#83, kroxylicious#88, kroxylicious#89 all have numbers conflicting with accepted
  proposals and have been allocated new sequential numbers (016-024)

Assisted-By: Claude Sonnet 4.5 <noreply@anthropic.com>
Signed-off-by: Keith Wall <kwall@apache.org>

Author: k-wall

proposals/README.md

@@ -0,0 +1,66 @@
+# Kroxylicious Proposals
+
+This repository lists proposals for the Kroxylicious project.
+
+## For Proposal Authors
+
+When creating a new proposal:
+
+1. Create your proposal PR with a temporary filename (e.g. `proposals/nnn-my-proposal.md`) based on the [template](./000-template.md).
+2. After your proposal PR is created, raise a **separate PR** updating this README file to:
+   - Allocate your proposal the next sequential number
+   - Add an entry in the "Open Proposals" table below
+   - Link to your proposal PR
+   - Announce your proposal on the mailing list (https://kroxylicious.io/join-us/mailing-lists/)
+3. Once the REAME PRs is merged, rename your proposal file to use the allocated number
+4. When your proposal is approved nd about to to be merged:
+   - Move your proposal from the "Open Proposals" table to the "Accepted Proposals" table
+   - Update the link to point to the merged file instead of the PR
+
+This process ensures proposal numbers are allocated in chronological order and avoids conflicts.
+
+## Open Proposals (Pull Requests)
+
+Proposals are numbered in chronological order by PR creation date.
+
+⚠️ **Note:** Some proposals have number collisions with accepted proposals and need to be renumbered:
+- PR #70 (currently 004) → should be 016
+- PR #82 (currently 007) → should be 017
+- PR #83 (currently 012) → should be 018
+- PR #85 (currently nnn) → should be 019
+- PR #88 (currently 014) → should be 020
+- PR #89 (currently 016) → should be 021
+- PR #92 (currently xxx) → should be 022
+- PR #93 (currently xxx) → should be 023
+- PR #94 (currently nnn) → should be 024
+
+| #  | Title                                                                 | PR |
+|:--:|:----------------------------------------------------------------------|:--:|
+| 24 | [Cleaning up TLS configurations](https://github.com/kroxylicious/design/pull/94) | [#94](https://github.com/kroxylicious/design/pull/94) |
+| 23 | [Request/Response Contextual Data API](https://github.com/kroxylicious/design/pull/93) | [#93](https://github.com/kroxylicious/design/pull/93) |
+| 22 | [Migrate Kroxylicious Operator to Strimzi v1 API](https://github.com/kroxylicious/design/pull/92) | [#92](https://github.com/kroxylicious/design/pull/92) |
+| 21 | [Virtual Cluster Lifecycle](https://github.com/kroxylicious/design/pull/89) | [#89](https://github.com/kroxylicious/design/pull/89) ⚠️ |
+| 20 | [Frontend Handler Refactoring & Client Session Context](https://github.com/kroxylicious/design/pull/88) | [#88](https://github.com/kroxylicious/design/pull/88) ⚠️ |
+| 19 | [Audit logging](https://github.com/kroxylicious/design/pull/85) | [#85](https://github.com/kroxylicious/design/pull/85) |
+| 18 | [Changing Active Proxy Configuration (Hot Reload)](https://github.com/kroxylicious/design/pull/83) | [#83](https://github.com/kroxylicious/design/pull/83) ⚠️ |
+| 17 | [Kroxylicious 1.0 and patch releases](https://github.com/kroxylicious/design/pull/82) | [#82](https://github.com/kroxylicious/design/pull/82) ⚠️ |
+| 16 | [A Routing API](https://github.com/kroxylicious/design/pull/70) | [#70](https://github.com/kroxylicious/design/pull/70) ⚠️ |
+
+## Accepted Proposals
+
+| #  | Title                                                                 |
+|:--:|:----------------------------------------------------------------------|
+| 15 | [Entity Isolation Filter](./015-entity-isolation.md) |
+| 14 | [Restrict Operator to a Configurable Set of Namespaces](./014-operator-namespace-restriction.md) |
+| 13 | [Upgrade Project JDK to Java 21](./013-upgrade-project-jdk-to-java-21.md) |
+| 11 | [Plugin API for selecting TLS client credentials for proxy-to-server connection](./011-plugin-api-to-select-tls-credentials-for-server-connection.md) |
+| 10 | [Extend the automatic discovery of bootstrap address feature to handle TLS listeners](./010-automatic-discovery-of-strimzi-bootstrap-server-tls.md) |
+| 9  | [Authorization Filter](./009-authorizer.md) |
+| 8  | [Resolve Topic Names from Topic IDs in the Filter Framework](./008-topic-name-lookup-facility.md) |
+| 7  | [Azure KMS Implementation](./007-azure-kms.md) |
+| 6  | [API to expose client SASL information to Filters](./006-filter-api-to-expose-client-sasl-info.md) |
+| 5  | [Filter API to expose client and server TLS info](./005-filter-api-to-expose-client-and-server-tls-info.md) |
+| 4  | [Terminology for Authentication](./004-terminology-for-authentication.md) |
+| 3  | [Improvements to Kroxylicious (Proxy) Metrics](./003-metric-improvements.md) |
+| 2  | [Automatically trigger a deployment rollout of affected proxies on Kubernetes config change](./002-Automaticly-reload-on-Kubernetes-config-change.md) |
+| 1  | [Kroxylicious Operator API (v1alpha)](./001-kroxylicious-operator-api-v1alpha.md) |